Recalls: Audi B7 A4 Cabriolet
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 A4 Cabriolet
Audi B7 A4 Cabriolet: Takata airbag recall
In August 2018, a recall was issued for Audi B7 A4 Cabriolet vehicles. The Takata driver’s airbag in these vehicles contained propellant wafers that could absorb moisture over time. In the event of a collision which triggered the driver’s airbag, excessive internal pressure could cause the metal airbag inflator housing to explode. This, in turn, would cause the metal fragments to be projected through the airbag cushion and into the cabin – these fragments posed a serious risk of injury and fatality. For the VINs of the recalled vehicles, please see PRA 2018/16949.
Problems and faults: Audi B7 A4 Cabriolet
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.
Carbon deposits (build-up) on intake valves
Audi’s naturally aspirated, direct injected petrol engines (such as the A4 Cabriolet’s 3.2 FSI) are considered susceptible to accumulating carbon deposits (or build up) on the intake valves. In these direct injection petrol engines, carbon deposits may accumulate on the stem and throat of the intake valve due to:
- the vaporisation of oil which is not trapped by the oil separator; or
- unburned fuel and exhaust gases that escape past the piston rings and enter the crankcase (‘blow-by’).
Since direct injection engines do not spray fuel on the backside of the intake valves, the detergent properties of the fuel cannot remove the carbon build up (as occurs in port injected engines). Symptoms of carbon deposits on the intake valve include difficulty starting the vehicle (hard starting), misfiring and misfire engine codes and reduced engine performance. Potentially, these deposits can result in damage to the catalytic converter and, for turbocharged engines, the turbocharger itself if bits of the deposit break off and enter the exhaust. To remove the carbon deposits, the intake must be removed and the valves cleaned manually. To reduce the incidence of carbon deposits, a common aftermarket measure is the fitment of an oil vapor catch can. The catch can receives dirty air from the crankcase via the Positive Crankcase Ventilation (PCV) valve, filters it and returns it to the intake manifold via the PCV port.
Audi B7 A4 Cabriolet 3.2 FSI: rough idle and hesitation
In November 2008, Audi issued technical service bulletin 2010890/8 for 2005-06 Audi B7 A4 Cabriolet 3.2 V6 FSI vehicles. In these vehicles, the driver may experience:
- A rough idle after a cold start;
- The engine may stumble or hesitate at slow initial acceleration after a cold start and under certain weather conditions; and,
- The engine may attempt to stall at idle when the transmission is shifted from Neutral or Park to Drive or Reverse when coolant temperature is above 80 degrees Celsius and the vehicle is stationary.
To fix, the Engine Control Module (ECM) was to be reprogrammed with new software.
Audi B7 A4 Cabriolet 3.2 FSI: low-pressure fuel system sensor
In March 2008, Audi issued technical service bulletin 2015106/4 for 2007-08 Audi B7 A4 Cabriolet 3.2 V6 FSI vehicles. In these vehicles, the Malfunction Indicator Lamp (MIL) may illuminate and the following diagnostic trouble codes (DTCs) may be logged –
- P310B: low-pressure fuel system regulation, fuel pressure outside tolerance; and,
- P129F: low-pressure fuel system, pressure too high.
According to the service bulletin, this condition may be caused by fuel intrusion into the low-pressure system fuel pressure sensor (G410), such that a false signal that was out of tolerance was sent to the controller. Subsequently, improvements were made to the G410 fuel pressure sensor.
Audi B7 A4 Cabriolet Multitronic (CVT): no drive or delayed drive
In January 2007, Audi issued technical service bulletin 2013280/1 for Audi B7 A4 Cabriolet with 01J continuously variable transmissions (CVTs, or Audi’s ‘Multitronic’) that were manufactured prior to May 2006. In these vehicles, the following conditions occur:
- No drive or delayed drive when ‘D’ or ‘R’ is selected. Furthermore, Diagnostic Trouble Code (DTC) P1743/18151 may be logged in the Transmission Control Module (TCM) fault memory; and/or,
- When accelerating from ret, an increased engine speed is necessary to move the vehicle.
According to the service bulletin, some seals for the CVT may have been damaged in production and leak after a short operating period (less than 20,000 kilometres), causing a loss of transmission oil pressure.
Audi B7 A4 Cabriolet Multitronic: emergency running mode and DTCs
In May 2007, Audi issued technical service bulletin 2012154/8 for 2006-07 Audi B7 A4 Cabriolet vehicles with 01J continuously variable transmissions (CVTs, Audi’s ‘Multitronic’). In these vehicles,
- The Malfunction Indicator Light (MIL) may illuminate;
- The vehicle may enter emergency running mode with gear indicator illumination inverted; and,
- Diagnostic Trouble Codes 17090-P0706 (transmission range sensor circuit range/performance) or 18201-P1793 (output speed sensor 2 circuit no signal) may be issued.
If either of the above Diagnostic Trouble Codes (DTCs) were logged, the Transmission Control Module was to be replaced.
B7 A4 Cabriolet 2.0 TFSI: intake flap motor & manifold runner position sensor
In March 2008, Audi issued technical service bulletin 2016868/2 for 2007 Audi B7 A4 Cabriolet 2.0 TFSI vehicles. In these vehicles,
- The Malfunction Indicator Light (MIL) may illuminate; and,
- One or more of the following Diagnostic Trouble Codes (DTCs) is stored in the Engine Control Module (ECM) data memory:
- DTC P0642: sensor voltage circuit A, low voltage;
- DTC P2004: intake manifold runner control bank 1, stuck open;
- DTC P2008: intake flap for airflow control, electrical malfunction;
- DTC P3137: intake manifold runner control circuit bank 1, basic settings not carried out; and,
- DTC P3138: intake flap for airflow control, control difference.
According to the service bulletin, this condition could be caused by:
- The ECM software; and/or,
- The intake flap motor V157 or Intake Manifold Runner Position Sensor G336 being inoperative (both are included in a single unit).
Updated ECM software was subsequently introduced, while the manufacturing process for the intake flap motor and intake manifold runner position sensor was improved.
Problems and faults: Audi B7 A4 Cabriolet
- 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.
- For the 1.8-litre turbocharged petrol engine, the throttle body control valve may sludge up, causing a very low or uneven idle.
