Overview

Commencing production in November 2016 and officially released in Australia in February 2017, the Audi B9 S4 and S4 Avant were compact executive sedans and wagons, respectively. Manufactured in Ingolstadt, the four-wheel drive Audi B9 S4 was powered by a 3.0-litre direct-injection turbocharged V6 petrol engine that was mated to an eight-speed automatic transmission. As such, the Audi B9 S4 and S4 Avant could accelerate from rest to 100 km/h in 4.7 and 4.9 seconds, respectively; over the combined ADR 81/02 test cycle, fuel consumption was 7.7 and 7.8 litres per 100 km.

Audi B9 S4: CWGD engine

The Audi B8 S4’s CWGD V6 engine had 84.5 mm bores and an 89.0 mm stroke for a capacity of 2995 cc. Key features of the CWGD engine included its aluminium alloy crankcase and cylinder head, grey cast iron cylinder liners, four valves per cylinder, variable intake and exhaust valve timing, variable exhaust valve timing, twin-scroll turbocharger, direct injection and compression ratio of 11.2:1. To reduce fuel consumption, the CWGD engine had:

• A Start-Stop system which enabled it to shut down as the vehicle was coming to rest; and,
• A free-wheel function which disengaged the engine from the driveline to reduce engine braking at speeds between 55 km/h and 160 km/h.

To avoid knock (i.e. uncontrolled detonation), the CWGD had a shorter compression phase relative to the expansion phase. According to Audi, the variable valvelift system enabled short intake valve opening times of 130 crankshaft degrees under part loads while simultaneously closing the intake valves early. At higher loads, the inlet valves could be shifted over to a camshaft contour with a longer opening time and larger valve stroke that maximised engine power.

The CWGD engine complied with Euro 6 emissions standards.

quattro all-wheel drive

The four-wheel drive ‘quattro’ system for the Audi B9 S4 was a purely mechanical system which utilised a self-locking central differential (designed as a planetary gear train). In normal conditions, the differential provided 60 per cent of the engine’s torque to the rear axle and 40 per cent to the front, i.e. a 40:60 front:rear torque split. Depending on the situation, however, up to 70 per cent of the engine’s torque could be transferred to the front and up to 85 per cent to the rear.

When cornering, the wheels on the inside of the corner were slightly braked before they could slip; according to Audi, this provided more precise, agile and stable handling. As an extra-cost option, the Audi S4 was offered with a sport differential which actively distributed drive forces between the rear wheels.

Dimensions and body

Based on the Audi B9 A4 , the Audi B9 S4 was 4726 mm long, 1842 mm wide, 1429 mm tall and has a 2822 mm long wheelbase. The B9 S4 Avant, however, was 19 mm longer (at 4745 mm), 34 mm lower (1395 mm) and has a 9 mm longer wheelbase (2831 mm). The Audi B9 S4 and S4 Avant had unladen weights of 1735 kg and 1810 kg, respectively. Boot capacity for the S4 sedan is 480 litres, while the S4 Avant had cargo capacity of 505 litres which increased to 1510 litres when the rear seats were folded.

Compared to the Audi B9 A4 , the Audi B9 S4 could be identified by its ‘aluminium look’ door mirror housings, strongly profiled sill trims, separating edge for the tailgate, S-specific rear bumper with black honeycomb grille, S-typical diffuser clip and four tailpipes for the dual-branch exhaust system.

Suspension

The Audi B9 S4 had five-link front suspension in which the upper links and integrated into the bodywork and the lower links are attached with rubber mounts to a hybrid steel/aluminium sub-frame. For the five-link rear suspension, the axle was insulated from the body by hydraulically damped axle mounts. To reduce mass, the axle links, pivot bearings and dampers stilts were made of forged aluminium. Compared to the B9 A4 , the standard S sport suspension was 23 mm lower.

As standard, the Audi B9 S4 had ‘Continuous Damping Control’ (CDC) shock absorbers which featured electromagnetically controlled valves in their pistons to control the flow of hydraulic fluid. For the CDC system, the central suspension control unit processed inputs from sensors measuring movement and acceleration (longitudinal and transverse) to control each shock absorbed individually; the driver could also adjust their behaviour by selecting from several modes.

Steering

The Audi B9 A4 had electromechanical power steering. As an extra-cost option, the B9 S4 was available with speed-dependent ‘dynamic steering’ which varies its ratio – by up to 100 per cent – according to the vehicle’s speed, steering angle and drive mode selected.

Safety equipment

Standard safety equipment for the Audi B9 S4 included dual front airbags, front rear side airbags, full-length curtain airbags (i.e. for front and rear occupants), ABS, electronic brake force distribution, brake assist, electronic stability control, traction control and front seatbelts with pre-tensioners and load limiters.

As standard, the Audi B9 S4 was fitted with ‘Audi pre sense city’. Operating at speeds up to 85 km/h, Audi pre sense city used a windscreen-mounted front camera to scan the road for other vehicles and pedestrians. If there was a risk of a collision, the driver would receive a series of warnings and, if the driver failed to respond, full braking force would be applied autonomously. At initial speeds of up to 40 km/h, collisions can be prevented; at higher speeds (up to 85 km/h), the severity of the collision would be reduced.

An extension of ‘Audi pre sense city’, the ‘Audi pre sense front’ system could prevent front-to-rear collisions or reduce their severity. In hazardous situations, the driver would receive warnings visual and acoustic warnings to apply the brakes, followed by a brief application of the brakes for a jolting effect to alert the driver. If the driver fails to respond, the S4 would decelerate to the greatest possible extent if the vehicle ahead of it is still moving.

Also fitted as standard, ‘Audi pre sense rear’ can warn of potential collisions from behind, warn following traffic by rapidly flashing the brake lights and activate the ‘Audi pre sense basic’ protection measures such as tightening the front seatbelts, and closing the windows and sunroof (where fitted).

The Audi B9 S4 was also fitted with the following active safety technologies –

• Adaptive Cruise Control (ACC): using two front radar sensors and the camera, ACC could maintain a specified distance – from five distances – between the S4 and the vehicle ahead. Furthermore, ‘Audi drive select’ could be used to adjust the rate of acceleration and other control dynamics;
• Stop&Go function: an extension of the, ‘Stop&Go’ operated at speeds of 60 km/h to apply the brakes and bring the vehicle to rest. Once traffic began moving, the Audi S4 would automatically accelerate;
• Traffic-jam assist: an extension of the ACC, traffic-jam assist function could take control of steering operations at speeds up to 65 km/h on ‘well-developed roads when traffic is congested.’ In doing so, traffic-jam assist used the lane markings and other vehicles on the road for orientation. When the traffic-jam assist function reached its limits – for example, when traffic is sparse or there is a sharp corner ahead – the driver had to take over steering. Hence, the system provided warnings at different levels;
• Predictive efficiency assistant: used navigation data to keep the driver informed about situations which required lower speed, such as corners, roundabouts, road junctions, gradients, city limits and speed limit signs. A corresponding alert would appear in the instrument cluster and/or Audi virtual cockpit and head-up display. For models with automatic transmissions, the system could also take over freewheeling of the automatic transmission in certain conditions;
• Avoidance assist: activated when the Audi S4 needed to avoid an obstacle to avert a collision. Using data from the front camera, the ACC and radar sensors, ‘avoidance assist’ could calculate the distance of the car ahead, its width and degree of offset. The brakes would be briefly applied to alert the driver of the potential danger and, once the driver started steering, the system would provide ‘support with the necessary lane changes with controlled interventions to the power steering’;
• Turning assist: active at speeds from 2 km/h to 10 km/h, ‘Turning assist’ could monitor oncoming traffic during right turns (for cars with right-hand drive). In hazardous situations, the brakes could be applied to bring the vehicle to rest. Turning assist operated once the driver activated the right-hand turn signal;
• Audi active lane assist: used the front camera to detect lane markings at speeds of 65 km/h and above. If the Audi S4 approached a lane marking without the driver having previously indicated, the electromechanical steering could provide an adjustment to bring the vehicle back into its lane. Using the MMI system, the driver could determine whether this system should be activated at all times or only before the lane marking is crossed. As an option, the driver could choose to have steering wheel vibrations as a warning signal;
• Audi side assist: operating at speeds above 15 km/h, Audi side assist used the two rear radar sensors to monitor traffic up to 70 metres behind the Audi S4. If another vehicle approached quickly or was in the driver’s blind spot, a warning LED in the housing of the appropriate door mirror would illuminate. If the driver activated the indicator to change lanes, the LED would blink rapidly to warn the driver;
• Rear cross-traffic assist: when reversing at low speeds, rear cross-traffic assist used the rear radar sensors to detect approaching traffic. If approaching traffic was detected which may cross the vehicle’s path, the driver received warnings (visual, acoustic and a brief, jolting application of the brakes);
• Exit warning: activated when the vehicle stopped moving and could warn occupants if vehicles were approaching from behind by illuminating red fibre optics in the door-opening mechanism as the doors were opened; and,
• Attention assist: monitored driver behaviour and issued a warning if the driver was assessed to be ‘inattentive’.

Brakes

The Audi S4 had 350 mm by 34 mm ventilated front disc brakes with six-piston fixed callipers and 330 mm by 22 mm ventilated rear disc brakes.

Features: Audi B9 S4

Standard features for the Audi B9 S4 included a 180 watt Audi sound system with ten speakers and a six-channel amplifier, digital radio tuner (DAB+), Audi music interface via USB including Audi smartphone interface, Bluetooth mobile phone connectivity and audio streaming, ‘Audi connect’ with in-car Wi-Fi hotspot and Google services, and Audi’s ‘MMI navigation plus’ system which consisted of an 8.3-inch colour display and a seven-inch instrument cluster display, live traffic updates, voice control, CD/DVD player, auxiliary inputs, two SDXC card readers and 10 GB flash memory. Furthermore, the ‘Audi smartphone interface’ could connect Apple or Android mobile devices via USB to approved apps via the MMI interface.

The Audi B9 S4 was also equipped with 8.5J x 19-inch ‘Audi Sport’ alloy wheels with 245/35 R19 tyres, power adjustable and heated front sports seats, combination leather and Alcantara seat upholstery, three-zone climate control air conditioning, LED headlights with LED daytime running lights, dusk-sensing headlights, high beam assist, rain-sensing wipers, a surround view camera system, 40:20:40 split and folding rear seats, a leather-wrapped steering wheel with gearshift paddles, remote central locking with proximity key, power adjustable and heated door mirrors with auto-dimming and folding function, power windows, driver’s seat memory settings, an auto-dimming interior mirror, a height and reach adjustable steering wheel, push-button start, ambient lighting, illuminated door sills, floor mats (front and rear), rear privacy glass, tyre pressure monitoring, a trip computer and an immobiliser.

As standard, the Audi S4 was also equipped with the following features –

• ‘Audi Virtual cockpit’: a fully configurable 12.3-inch high resolution display within the instrument cluster;
• Audi parking system plus: front and rear parking sensors and a visual display; and,
• Park assist: provided automated steering for parallel or perpendicular parking manoeuvres.

Features: Audi B9 S4 Avant

The Audi B9 S4 Avant was further equipped with anodised aluminium roof rails, a power-operated tailgate, power-retracting luggage cover, a sensor-controlled luggage compartment release and an extendable partition net for the luggage compartment.

Brochure and specifications

• Brochure: Audi B9 S4 (February 2017)
• Specifications: Audi B9 S4 Sedan (February 2017)
• Specifications: Audi B9 S4 Avant (February 2017)

Review: Audi B8.I S4 (2009-12)

Overview

Released in June 2009, the Audi B8 S4 was a compact executive, sports sedan. Manufactured in Ingolstadt, Germany, the Audi S4 was powered by a 3.0-litre supercharged V6 petrol engine that was mated to a seven-speed double clutch transmission (Audi’s ‘DSG’) that drove all four wheels via Audi’s ‘quattro’ system.

3.0 TFSI V6 engine

The S5 Sportback’s 3.0-litre CAKA TFSI V6 engine had an aluminium-silicon alloy crankcase, a die-forged steel crankshaft, a cast aluminium cylinder head, chain-driven double overhead camshafts, variable intake camshaft timing over a range of 42 degrees, four valves per cylinder (including chrome plated exhaust valves with sodium-filled stems), direct fuel injection (Audi’s ‘Fuel Stratified Injection’ or FSI) and a compression ratio of 10.3:1.

The 3.0 TFSI V6 engine featured a Roots-type positive displacement supercharger – produced by Eaton – that was positioned in the ‘V’ of the cylinder banks. The supercharger had twin four-lobe rotors and could force intake air into the combustion chambers at a maximum boost pressure of up to 0.8 bar.

Dimensions and suspension

Compared to the Audi B7 S4 , the B8 S4 was 131 mm longer (at 4717 mm), 45 mm wider (1826 mm), 9 mm lower (1406 mm) and had a 160 mm longer wheelbase (2811 mm). Like the Audi B8 A4 , on which it was based, the S4 had five-link front suspension with unequal length wishbones and self-tracking trapezoidal rear suspension. Relative to the A4, however, the S4 had firmer shock absorber settings, stiffer bearings for the controls arms and the body was lowered by 20 mm.

quattro

The Audi B8 S4’s quattro four-wheel drive system consisted of a Torsen T3 differential which provided a default 40:60 front:rear torque split. If traction was lost, up to 80 per cent of the engine’s torque could be directed to either the front or rear axles. The system also included an open front differentials with an electronic differential locks which could brake a spinning wheel to enable cross-axle torque transfer. The B8 S4 also introduced a torque vectoring rear axle which operated by selectively distributing torque to the rear wheels to generate yaw and thereby correct over- or under-steer.

Safety equipment

Standard safety equipment for the B8 S4 included dual front airbags, front and rear side airbags, full-length curtain airbags (i.e. for front and rear occupants), ABS, electronic brake force distribution, brake assist, electronic stability control, traction control and front seatbelts with pretensioners and load limiters.

Brakes

The Audi B8 S4 had ventilated front and rear disc brakes, measuring 345 mm at the front (diameter) and 330 mm at the rear.

Features: B8 S4

Standard features for the Audi B8 S4 included 18-inch ‘S-design’ alloy wheels, a ten speaker stereo with a six-disc CD player, MP3-compatibility and auxiliary inputs, satellite navigation system, dual-zone climate control air conditioning, power adjustable front sports seats, leather seat trim, cruise control, directional bi-xenon headlights with LED running lights, front and rear fog lamps, front and rear parking sensors, automatic headlights, rain-sensing wipers, a leather-wrapped steering wheel with gearshift paddles, Bluetooth connectivity with voice recognition, remote central locking with proximity key, power windows and heated mirrors, a power-operated park brake, tilt and telescopic steering wheel adjustment, tyre pressure monitoring, ambient lighting, 12 volt power outlets, a trip computer, an alarm and immobiliser.

Related links

• Press Kit: Audi B8.I S4 (May 2009)
• Specifications: Audi B8.I S4 (May 2009)

Review: Audi B8.II S4 and S4 Avant (2012-15)

Overview

Released in July 2012, the Audi B8 Series II (B8.II) S4 range was expanded to include the S4 Avant (wagon). Visually, the B8.II S4 could be identified by its new bumpers with angular air inlets, revised headlights, flat front fog lights, more pronounced bonnet arches and tapered grille corners. Inside, the Multi Media Interface (‘MMI’) controls were revised for greater ease of use.

Compared to its B8.I predecessor, the B8.II S4 achieved significant fuel economy improvements due to the introduction of:

• a ‘start-stop’ system which could shut down the engine when stationary in traffic;
• a recuperation system which converted kinetic energy into electrical energy when the vehicle was coasting or braking; and,
• a new electrochmechanical power steering system.

Safety equipment and features

Compared to its B8.I predecessor, standard safety equipment and features for the B8.II S4 sedan were largely unchanged. Compared to the sedan, the S4 Avant was further equipped with aluminium roof rails and a power-operated tailgate.

Related links

• Specifications: Audi B8.II S4 (June 2012)
• Wikipedia.org: Audi B8 S4

Overview

Released in December 2003, the Audi B6 S4 was initially available as a sedan, with Avant (wagon) models following in August 2004. Manufactured in Ingolstadt, Germany, the Audi S4 was powered by a 4.2-litre V8 petrol engine that was mated to either a six-speed automatic or manual transmission and drove all four wheels via Audi’s quattro system.

4.2 V8 engine

The Audi B6 S4’s 4.2-litre BBK V8 petrol engine had a cast aluminium alloy block, die-forged steel crankshaft that operated on five main bearings, a cast aluminium alloy cylinder head, double overhead camshafts per cylinder bank (chain-driven), five valves per cylinder actuated by roller rocker cam followers, variable intake camshaft timing, a variable intake manifold, a compression ratio of 11.0:1 and maximum engine speed of 7200 rpm.

Although based on the AQH/AVP/AYS/BCS engines in the Audi D2 S8 , the length of the BBK engine was reduced by 52 mm to 464 mm so that it could fit in the engine bay of the Audi B6 S4. This reduction in length was achieved by transferring the chain drive to the clutch side of the engine and using chain-driven camshafts.

With the six-speed manual transmission, the S4 sedan could accelerate from rest to 100 km/h in 5.6 seconds.

Dimensions and suspension

Compared to the Audi B5 S4 , the B6 S4 sedan was 63 mm longer (at 4546 mm), 33 mm wider (1766 mm), 32 mm taller (1428 mm) and had a 30 mm longer wheelbase (2645 mm). Furthermore, the B6 S4 Avant had the same dimensions as the B6 sedan. The B6 S4 and S4 Avant had four-link front suspension with unequal length wishbones and self-tracking trapezoidal link rear suspension.

quattro

The Audi B6 S4’s quattro four-wheel drive system consisted of a Torsen T2 centre differential. In normal conditions, the system provided a 50:50 front:rear torque split but up to two-thirds of the engine’s torque could be directed to either axle if traction was lost. The system also included open front and rear differentials with electronic differential locks which could brake spinning wheels to enable cross-axle torque transfers at speeds of up to 80 km/h.

Safety equipment

Standard safety equipment for the Audi B6 S4 included dual front airbags, front and rear side airbags, full-length curtain airbags (i.e. for front and rear occupants), ABS, electronic brake force distribution, brake assist, electronic stability control, traction control and front seatbelts with pretensioners and load limiters.

Brakes

The Audi S4 had radially ventilated front and rear disc brakes; the 345 mm (diameter) by 30 mm (width) front discs and 300 mm by 22 mm rear discs were both fitted with single-piston sliding calipers.

Features

Standard features for the Audi B6 S4 included 18-inch Avus III alloy wheels with 235/40 R18 Y Contintental tyres, a ten speaker stereo with a 10-disc CD changer, dual-zone climate control air conditioning, combination Alcantara/leather upholstery, power adjustable Recaro front seats, xenon headlights with washers, front and rear fog lights, rear parking sensors, automatic headlights, a leather-wrapped steering wheel, split and folding rear seats, remote central locking, power windows and heated mirrors, tilt and telescopic steering wheel adjustment, an alarm and an immobiliser.

Related links

• Technical Specifications: Audi B6 S4 (October 2003)
• Wikipedia.org: Audi B6 S4

Overview

Released in November 2005, the Audi B7 S4 was a compact executive, sports sedan. Manufactured in Ingolstadt, the Audi B7 S4 was powered by a 4.2-litre V8 petrol engine that was mated to a six-speed automatic transmission that drove all four wheels via Audi’s quattro system.

4.2 V8 engine

The Audi B7 S4’s 4.2-litre BBK V8 petrol engine had a cast aluminium alloy block, die-forged steel crankshaft that operated on five main bearings, a cast aluminium alloy cylinder head, double overhead camshafts per cylinder bank (chain-driven), five valves per cylinder actuated by roller rocker cam followers, variable intake camshaft timing, a variable intake manifold, a compression ratio of 11.0:1 and maximum engine speed of 7200 rpm.

Although based on the AQH/AVP/AYS/BCS engines in the Audi D2 S8 , the length of the BBK engine was reduced by 52 mm to 464 mm so that it could fit in the engine bay of the Audi B6 S4. This reduction in length was achieved by transferring the chain drive to the clutch side of the engine and using chain-driven camshafts.

With a kerb weight of 1705 kg, the B7 S4 could accelerate from rest to 100 km/h in 5.8 seconds.

Dimensions and suspension

Compared to the Audi B6 S4 , the B7 S4 was 40 mm longer (at 4586 mm), 15 mm wider (1781 mm), 13 mm lower (1415 mm) and had a 6 mm longer wheelbase (2651 mm). Like the B7 A4 on which it was based, the B7 S4 had four-link front suspension with unequal length wishbones and self-tracking trapezoidal link rear suspension.

quattro

Like its B6 predecessor, the Audi B7 S4’s quattro four-wheel drive system initially utilised a Torsen T2 centre differential. In normal conditions, the system provided a 50:50 front:rear torque split but up to two-thirds of the engine’s torque could be directed to either axle if traction was lost. The system also included open front and rear differentials with electronic differential locks which could brake spinning wheels to enable cross-axle torque transfers.

From 2007, however, a Torsen T3 differential was fitted which provided a default 40:60 front:rear torque split. If traction was lost, up to 80 per cent of the engine’s torque could be directed to either the front or rear axles.

Safety equipment

Standard safety features for the Audi B7 S4 included dual front airbags, front and rear side airbags, full-length curtain airbags (i.e. for front and rear occupants), ABS, electronic brake force distribution, brake assist, electronic stability control, traction control, active front seat head restraints and front seatbelts with pretensioners and load limiters.

Brakes

The Audi S4 was fitted with radially ventilated front and rear disc brakes; the 345 mm (diameter) by 30 mm (width) front discs and 300 mm by 22 mm rear discs were both fitted with single-piston sliding calipers.

Features

Standard features for the Audi B7 S4 included 18-inch alloy wheels, a ten speaker sound system with a six-disc CD player, dual zone climate control air conditioning, cruise control, power adjustable Recaro front seats, Silk Nappa leather upholstery, directional bi-xenon headlights, front and rear fog lamps, automatic headlights, rear parking sensors, rain-sensing wipers, split and folding rear seats, remote central locking with proximity, power windows and heated mirrors, tilt and telescopic steering wheel adjustment, a motion-sensing alarm and an immobiliser.

Related links

• Wikipedia.org: Audi B7 S4

Overview

Released in November 1999, the Audi B5 Series II (B5.II) S4 and S4 Avant were high-performance, compact executive sedans and wagons respectively. Manufactured in Ingolstadt, Germany, the all-wheel drive Audi B5 S4 and S4 Avant were powered by a 2.7-litre twin-turbocharged V6 petrol engine that was mated to a six-speed manual transmission, driving all four wheels via Audi’s ‘quattro’ four-wheel drive system.

2.7-litre biturbo V6 engine

The Audi B5 S4’s 2.7-litre AZB/AGB V6 petrol engine had a cast iron engine block, a die-forged steel crankshaft, forged pistons, a cast aluminium alloy cylinder heads, double overhead camshafts. five valves per cylinder actuated by hydraulic tappets, variable intake camshaft timing over a range of 22 degrees, two parallel water-cooled Borg Warner K03-series turbochargers, two side-mounted air-to-air intercoolers and a compression ratio of 9.3:1. Maximum engine speed for teh AZB/AGB engine was 6800 rpm.

Dimensions and suspension

Compared to the Audi B5 A4 on which it was based, the S4 sedan was 4 mm longer (at 4483 mm), the same width (1715 mm), 19 mm lower (1395 mm) and had the same length wheelbase (2615 mm); the S4 Avant had the same dimensions. The S4 had four-link front suspension and unequal length double wishbone rear suspension (with the lower control arms mounted to a subframe which included the differential housing).

quattro and electronic differential locks

The Audi B5 S4 and S4 Avant were fitted with a fourth generation permanent four-wheel drive quattro system which utilised a T-2 Torsen centre differential. In normal conditions, the system provided a 50:50 front:rear torque split. However, the front and rear axles were fitted with electronic differential locks which could apply the brakes to spinning wheels – at speeds of up to 80 km/h – with the effect of locking the differential and transferring torque to the opposing axle.

Safety equipment

Standard safety equipment for the Audi S4 and S4 Avant included dual front airbags, front side airbags, ABS, electronic brake force distribution, electronic stability control, traction control and front and outer rear seatbelts with pretensioners.

Brakes

The Audi B5 S4 and S4 Avant had 321 mm by 30 mm ventilated front brake disc with two-piston Lucas HP2 brake calipers and 256 mm by 22 mm rear discs with Lucas single-piston sliding calipers.

Features

Standard features for the Audi S4 included 17-inch six-arm Avus alloy wheels with 225/45 ZR17 performance tyres, a six speaker Bose sound system with a ten-disc CD changer, climate control air conditioning, power adjustable Recaro front seats, leather upholstery, cruise control, front and rear fog lights, xenon headlights with washers, split and folding rear seats, a leather-wrapped steering wheel, remote central locking, power windows and mirrors, a height and reach adjustable steering wheel, an alarm and immobiliser.

Beyond this, the S4 Avant added rear parking sensors.

Related links

• Wikipedia.org: Audi B5 S4

Recalls: Audi B9 S4

Overview

Manufacturers, or importers, issue recalls for defects or faults which have the potential to cause injury. Generally, manufacturers will inform the original buyers if their vehicle is subject to a recall and of the steps required to remedy the defect or fault. Please note that the recalls below (if any) are for Australian-delivered vehicles only. Furthermore, the number of recalls should not be taken as an indication of a model’s reliability or its safety more generally.

Recalls: Audi B9 S4

2019 model year Audi B9 S4: shock absorber failure

In June 2019, recall campaign 40O6 was issued for Audi B9 S4 vehicles because the shock absorber may fail and cause separation of suspension components. If the vehicle was in motion, the driver may lose control and this would pose a hazard to vehicle occupants and other road users. For the VINs of the recalled vehicles, please see PRA 2019/17595.

2018-21 Audi B9 S4: seatbelt warning may operate occasionally

In July 2021, recall campaign 90P5 was issued for 2018-21 Audi B9 S4 vehicles. The seatbelt warning (acoustic warning tone and visual display) may operate occasionally, rather than continuously, in circumstances such as a seatbelt not fastened or unfastened while the vehicle was moving. If the warning did not sound continuously, a seatbelt may be unbuckled without the driver being informed. In the event of a collision, this condition increased the risk of injury to vehicle occupants. For the VINs of the recalled vehicles, please see REC-001650.

2019-21 Audi B9 S4: rear axle nuts could break and cause loss of control

In September 2021, recall campaign 42L1 was issued for 2019-21 Audi B9 S4 vehicles. Some nuts fitted to the rear axle assembly did not meet manufacturing specifications and could therefore break. A broken nut may lead to increased movement between the wishbone and hub carrier, and a change in the wheel alignment on the rear axle. These conditions could cause sudden and uncontrollable movement of the rear axle, thereby increasing the risk of injury and death to vehicle occupants and other road users. For the VINs of the recalled vehicles, please see REC-001665.

2019-21 Audi B9 S4: misalignment of rear axle from previous recall

In March 2022, recall campaign 42L5 was issued for 2019-21 Audi B9 S4 vehicles. The previous replacement of the rear axle clamping nuts as part of recall 42L1 may have caused misalignment of the rear axle assembly; this could result in excessive wear to the rear tyres, and may result in a sudden flat tyre and subsequent loss of vehicle control. These circumstances increased the risk of a collision and injury to vehicle occupants and other road users. For the VINs of the recalled vehicles, please see REC-005076.

Problems and faults: Audi B9 S4

Overview

This section identifies potential problems, causes and fixes based on the experiences of owners and repairers, online sources and technical service bulletins. This information is provided solely for reference purposes and AustralianCar.Reviews recommends that only properly qualified persons carry out repairs or modifications. Furthermore, the number of items below should not be taken as an indicator of a model’s reliability or the frequency with which they may occur.

To report a problem or fault to the AustralianCar.Reviews team, please use the Contact Us form. Note that AustralianCar.Reviews does not offer advice on automotive problems or disputes; such enquiries will not receive a reply. For vehicles purchased from dealers after 1 January 2011, please see our Australian Consumer Law fact sheet.

Problems and faults: Audi B9 S4

No troubleshooting information is currently available for the Audi B9 S4.

Recalls: Audi B6 S4

Overview

Manufacturers, or importers, issue recalls for defects or faults which have the potential to cause injury. Generally, manufacturers will inform the original buyers if their vehicle is subject to a recall and of the steps required to remedy the defect or fault. Please note that the recalls below (if any) are for Australian-delivered vehicles only. Furthermore, the number of recalls should not be taken as an indication of a model’s reliability or its safety more generally.

Recalls: Audi B6 S4

No recall information is available for the Audi B6 S4. To search for recalls of Audi models, please visit Product Safety Recalls Australia: Audi.

Problems and faults: Audi B6 S4

Overview

This section identifies potential problems, causes and fixes based on the experiences of owners and repairers, online sources and technical service bulletins. This information is provided solely for reference purposes and AustralianCar.Reviews recommends that only properly qualified persons carry out repairs or modifications. Furthermore, the number of items below should not be taken as an indicator of a model’s reliability or the frequency with which they may occur.

To report a problem or fault to the AustralianCar.Reviews team, please use the Contact Us form. Note that AustralianCar.Reviews does not offer advice on automotive problems or disputes; such enquiries will not receive a reply. For vehicles purchased from dealers after 1 January 2011, please see our Australian Consumer Law fact sheet.

Audi B6 S4: BBK V8 timing chain rattle

For the Audi S4’s 4.2-litre BBK V8 engine, the cam adjusters, tensioners and guides are susceptible to wear. As per the table below, this can cause camshaft over-advance codes to be issued, a rattling noise on start-up, engines misfires, a lack of performance and the vehicle to enter ‘limp home’ mode.

By removing the rear timing covers, the cam adjusters can be replaced without removing the engine from the engine bay. Replacement of the tensioners and guides, however, requires the engine to be removed from the engine bay since the chain drive is located at the rear of the engine.

Please note that while not all BBK engines have experienced these problems, failures have occurred at mileages from as little as 60,000 kilometres. To extend the life of the tensioner guides, frequent oil changes with high quality oil are recommended. For a discussion of this problem, please see Audizine: B6/B7 S4 Timing Chain FAQ.

Audi B6 S4: noise when shifting to/from fourth gear

In December 2006, Audi issued technical service bulletin 2013023/1 for 2004-05 Audi B6 S4 quattro vehicles because a chirping, hooting or squeaking noise may be heard when shifting to and from fourth gear. Furthermore, shudder may be experienced during the control phase of the torque converter clutch.

According to the service bulletin, the torque converter clutch briefly generated vibrations/shuddering during the control phase of the converter control/converter close. To fix,

• The transmission control unit was to be reprogrammed;
• The automatic transmission fluid was to be drained, filled, flushed and re-filled with ATF specification ‘G 055162A2’ (blue); and,
• An adaptation drive performed.

Problems and faults: Audi B6 S4

• The anti-lock braking system (ABS) may activate unnecessarily under normal to light braking pressure due to cracks in tone/exciter rings (rings on the outer CV shaft that measure wheel rotation).
• When the oil filter is removed, the oil cooler is susceptible to turning – this may damage the coolant lines and cause a coolant leak.
• Water may leak into a wiring harness near the A-pillar, causing problems with the remote central locking, power windows, issuing a ‘door ajar’ warning when the doors are shut and the interior lights staying on.

Recalls: Audi B7 S4

Overview

Manufacturers, or importers, issue recalls for defects or faults which have the potential to cause injury. Generally, manufacturers will inform the original buyers if their vehicle is subject to a recall and of the steps required to remedy the defect or fault. Please note that the recalls below (if any) are for Australian-delivered vehicles only. Furthermore, the number of recalls should not be taken as an indication of a model’s reliability or its safety more generally.

Recalls: Audi B7 S4

Audi B7 S4: Takata airbag recall

In December 2018, recall campaign 69R7 was issued for Audi B7 S4 vehicles. These vehicles had Takata front passenger airbags and the propellant wafers in these airbags could absorb moisture over time. In the event of airbag deployment, excessive internal pressure could cause the metal inflator housing to rupture and metallic fragments could be projected through the airbag cushion towards vehicle occupants – these fragments posed a risk of serious injury and fatality. For the VINs of the recalled vehicles, please see PRA 2018/17210.

Problems and faults: Audi B7 S4

Overview

This section identifies potential problems, causes and fixes based on the experiences of owners and repairers, online sources and technical service bulletins. This information is provided solely for reference purposes and AustralianCar.Reviews recommends that only properly qualified persons carry out repairs or modifications. Furthermore, the number of items below should not be taken as an indicator of a model’s reliability or the frequency with which they may occur.

To report a problem or fault to the AustralianCar.Reviews team, please use the Contact Us form. Note that AustralianCar.Reviews does not offer advice on automotive problems or disputes; such enquiries will not receive a reply. For vehicles purchased from dealers after 1 January 2011, please see our Australian Consumer Law fact sheet.

Audi B7 S4: BBK V8 timing chain rattle

For the Audi S4’s 4.2-litre BBK V8 engine, the cam adjusters, tensioners and guides are susceptible to wear. As per the table below, this can cause camshaft over-advance codes to be issued, a rattling noise on start-up, engines misfires, a lack of performance and the vehicle to enter ‘limp home’ mode.

By removing the rear timing covers, the cam adjusters can be replaced without removing the engine from the engine bay. Replacement of the tensioners and guides, however, requires the engine to be removed from the engine bay since the chain drive is located at the rear of the engine.

Please note that while not all BBK engines have experienced these problems, failures have occurred at mileages from as little as 60,000 kilometres. To extend the life of the tensioner guides, frequent oil changes with high quality oil are recommended. For a discussion of this problem, please see Audizine: B6/B7 S4 Timing Chain FAQ.

Audi B7 S4: noise when shifting to/from fourth gear

In December 2006, Audi issued technical service bulletin 2013023/1 for 2005-06 Audi B7 S4 quattro vehicles because a chirping, hooting or squeaking noise may be heard when shifting to and from fourth gear. Furthermore, shudder may be experienced during the control phase of the torque converter clutch.

According to the service bulletin, the torque converter clutch briefly generated vibrations/shuddering during the control phase of the converter control/converter close. To fix,

• The transmission control unit was to be reprogrammed;
• The automatic transmission fluid was to be drained, filled, flushed and re-filled with ATF specification ‘G 055162A2’ (blue); and,
• An adaptation drive performed.

Audi B7 S4: misfires and ignition coils

In December 2006, Audi issued technical service bulletin 2013623/1 for 2005-07 Audi B7 S4 vehicles with VINs in the range 8E 5A 400500 to 8E 7A 086400. In these vehicles,

• The Malfunction Indicator Light (MIL) may be flashing or constantly illuminated; and,
• Diagnostic Trouble Codes (DTCs) for misfire in one or more cylinders (P0300 to P0312, depending on the engine) are stored in the Engine Control Module (ECM).

According to the service bulletin, the misfire could be caused by the ingress of moisture in the ignition coils. Furthermore, new ignition coils supplied by Powertrain Pulse ERA were installed in production.

Problems and faults: Audi B7 S4

• The anti-lock braking system (ABS) may activate unnecessarily under normal to light braking pressure due to cracks in tone/exciter rings (rings on the outer CV shaft that measure wheel rotation).
• When the oil filter is removed, the oil cooler is susceptible to turning – this may damage the coolant lines and cause a coolant leak.
• Water may leak into a wiring harness near the A-pillar, causing problems with the remote central locking, power windows, issuing a ‘door ajar’ warning when the doors are shut and the interior lights staying on.

Recalls: Audi B8 S4

Overview

Manufacturers, or importers, issue recalls for defects or faults which have the potential to cause injury. Generally, manufacturers will inform the original buyers if their vehicle is subject to a recall and of the steps required to remedy the defect or fault. Please note that the recalls below (if any) are for Australian-delivered vehicles only. Furthermore, the number of recalls should not be taken as an indication of a model’s reliability or its safety more generally.

Recalls: Audi B8 S4

2011-14 Audi B8 S4: airbag may not inflate correctly

In October 2014, a recall was issued for Audi B8 S4 vehicles that were manufactured from November 2011 to October 2014 (inclusive). In these vehicles, the front airbags may not inflate correctly in the event of an accident. If the airbags did not deploy correctly, there was an increased risk of injury to the front occupants during a collision. As part of the recall, a software update was to be applied to the airbag control unit (PRA 2014/14402).

2011-12 Audi B8 S4 3.0 TFSI: fuel leak

In January 2015, a recall was issued for Audi B8 S4 models with the 3.0 TFSI engine that were manufactured from April 2011 to April 2012 (inclusive). In these vehicles, a fuel leak may occur at the connection between the fuel rail and the injector. If this occurred, the owner may detect a fuel smell from the engine compartment and leaking fuel could pose a fire hazard in the presence of an ignition source. As part of the recall, the fuel rail was to be replaced and a reinforced retaining bracket fitted (PRA 2015/14530).

2013-18 Audi B8 S4 3.0 TFSI: fuel leak

In March 2019, recall campaign 24DP was issued for Audi B8 S4 vehicles that had 3.0 TFSI EA837 evo engine and were manufactured between September 2013 and April 2018. In these vehicles, fuel may escape from one or both low-pressure fuel rails. In the presence of an ignition source, the fuel could ignite and pose a fire hazard; petrol fumes may also be noticed in the cabin. For the VINs of the recalled vehicles, please see PRA 2019/17395.

Problems and faults: Audi B8 S4

Overview

This section identifies potential problems, causes and fixes based on the experiences of owners and repairers, online sources and technical service bulletins. This information is provided solely for reference purposes and AustralianCar.Reviews recommends that only properly qualified persons carry out repairs or modifications. Furthermore, the number of items below should not be taken as an indicator of a model’s reliability or the frequency with which they may occur.

To report a problem or fault to the AustralianCar.Reviews team, please use the Contact Us form. Note that AustralianCar.Reviews does not offer advice on automotive problems or disputes; such enquiries will not receive a reply. For vehicles purchased from dealers after 1 January 2011, please see our Australian Consumer Law fact sheet.

Audi B8 S4: 7sp DL501 ‘S Tronic’ transmission – mechatronic and clutch faults

For 2008 to 2010 Audi vehicles with seven-speed ‘S Tronic’ DL501 (part code prefix: 0B5) double-clutch transmissions, there have been reports of:

• Mechatronic units that become faulty and require replacement; and,
• Premature wear of the dual multi-plate clutches that prevents them from engaging properly.

About the ‘S Tronic’ DL501 double clutch transmission

From late 2008, the seven-speed ‘S Tronic’ DL501 (part code prefix: 0B5) double-clutch transmission was introduced in Audi vehicles that had longitudinally-mounted engines – this includes the B8 A4, B8 S4, 8R Q5, 8T3 A5 Coupe, 8F7 A5 Cabriolet, 8F7 S5 Cabriolet, 8TA A5 Sportback and 8TA S5 Sportback.In the DL501 ‘S tronic’ transmission, torque is transmitted through the transmission plate to the dual-mass flywheel, and then to the electro-hydraulically controlled dual clutches which selectively operate the even or odd numbered gears.

S Tronic: faulty Mechatronic unit – ‘gearbox malfunction’ and other symptoms

Acting as the central gearbox control unit, the Mechatronic system combines the electro-hydraulic control unit (actuators), the electronic control unit and some sensors into a single unit. The mechatronic system performs the following functions:

• Regulation of oil pressure in the hydraulic system;
• Engagement of the dual clutches;
• Regulation of clutch temperature;
• Shift point selection;
• Regulation of gearbox control;
• Communication with other control units;
• Limp-home programs; and,
• Self-diagnostics.

Symptoms of a faulty Mechatronic unit include:

• Dashboard warnings such as ‘gearbox malfunction, you can continue driving in restricted mode’, ‘gearbox malfunction (no reverse)’ or similar. This message appears because clutch temperature has been calculated to be in a critical temperature range that can cause damage – around 160 degrees Celsius – and an entry will be made in the fault memory;
• Difficulty engaging drive or reverse gears (including ‘hard’ or abrupt gear shifts);
• The vehicle can only be driven in gears 1, 3, 5 and 7, and reverse cannot be engaged. Since the larger outer clutch is used for the odd-numbered gears and reverse, an inability to engage the even gears is due to an inability of the Mechatronic unit to engage the smaller inner clutch;
• The vehicle can only be driven in gears 2, 4, 6 and reverse. This indicates an inability of the Mechatronic unit to engage the larger outer clutch; and,
• ‘Hard’ or abrupt downshifts, especially when the gearbox is hot.

For these symptoms, it is recommended that the Mechatronic unit be repaired as soon as possible to prevent further damage – a Mechatronic repair kit was developed by Audi for this purpose. If further damage occurs, either:

• The Mechatronic unit requires replacement; or,
• The entire transmission (including the Mechatronic unit) requires replacement.

S Tronic: premature wear of multi-plate clutches

It is understood that the multi-plate clutches for the seven-speed ‘S Tronic’ transmission may wear prematurely and this can prevent them from engaging properly. Symptoms of clutch damage include:

• ‘Jerky’ performance where drive torque is transmitted in a stop/start or irregular fashion;
• Either of the clutches slipping;
• Loss of drive torque (in forward or reverse); and,
• Difficulty engaging drive or reverse gears (including ‘hard’ or abrupt gear shifts).

Problems and faults: Audi B8 S4

• The air conditioner may stop working due to the air conditioning temperature/pressure switch failing.
• The brakes may make a moaning or murmuring sound at low speeds or when turning at low speeds – this may be due to a faulty caliper piston seal that does not retract the brakes sufficiently.
• If something other than the ignition key (e.g. the wrong key) is inserted into the ignition lock, the remote keys will not work. For vehicles with the ‘Advanced’ key, the start/stop button will not work and the boot will not release.
• The parking lights may stay on permanently if the system is ‘awakened’ (e.g. a remote keyless entry unlock command) while in the ‘fall-asleep’ mode, requiring the control module to be reprogrammed.
• The 12-volt power outlets may not work due to a problem with the software in the convenience control module – reprogramming may also correct other problems such as remote keyless entry and the boot light not illuminating.
• The door seals may come loose due to poor adhesive and require replacement.

Recalls: Audi B5 S4

Overview

Manufacturers, or importers, issue recalls for defects or faults which have the potential to cause injury. Generally, manufacturers will inform the original buyers if their vehicle is subject to a recall and of the steps required to remedy the defect or fault. Please note that the recalls below (if any) are for Australian-delivered vehicles only. Furthermore, the number of recalls should not be taken as an indication of a model’s reliability or its safety more generally.

Recalls: Audi B5 S4

2000 model year Audi B5 S4: Takata airbag and vehicle buyback

In December 2019, recall campaign 69AE was issued for 2000 model year Audi B5 S4 vehicles. These recalled vehicles had Takata airbags and, over time, moisture could enter the airbag inflators and degrade the airbag propellant. If this occurred, deployment of the airbag could cause the airbag inflator housing to rupture and project metal fragments into the vehicle’s cabin – these fragments posed a serious risk of injury and fatality. The airbag could also under-inflate and not protect the driver as intended. As part of this recall, Audi Australia would offer to purchase the registered vehicle from the owner at present market value (i.e. as determined by a third party valuer appointed by Audi). Due to the age of the vehicles, replacement airbag inflators were not available. For the VINs of the recalled vehicles, please see PRA 2019/18002.

1999-01 Audi B5 S4 with three-spoke steering wheel: Takata airbag recall

In November 2021, recall campaign 69CJ was issued for 1999-01 Audi B5 S4 vehicles. The propellant in the gas generator of the Takata NADI 5-AT airbag that was fitted to certain vehicles with three-spoke steering wheels may degrade over time. As a result, the driver’s airbag may deploy with reduced force and this could increase the risk of injury to vehicle occupants in the event of a collision. For the VINs of the recalled vehicles, please see REC-004987.

Problems and faults: Audi B5 S4

Overview

This section identifies potential problems, causes and fixes based on the experiences of owners and repairers, online sources and technical service bulletins. This information is provided solely for reference purposes and AustralianCar.Reviews recommends that only properly qualified persons carry out repairs or modifications. Furthermore, the number of items below should not be taken as an indicator of a model’s reliability or the frequency with which they may occur.

To report a problem or fault to the AustralianCar.Reviews team, please use the Contact Us form. Note that AustralianCar.Reviews does not offer advice on automotive problems or disputes; such enquiries will not receive a reply. For vehicles purchased from dealers after 1 January 2011, please see our Australian Consumer Law fact sheet.

Problems and faults: Audi B5 S4

No troubleshooting information is currently available for the Audi B5 S4.