Recalls: Audi C6 S6
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 C6 S6
Audi C6 S6: Takata airbag recall
In December 2018, recall campaign 69R7 was issued for Audi C6 S6 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 C6 S6
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 S6’s 5.2 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 C6 S6: low-pressure fuel system sensor
In March 2008, Audi issued technical service bulletin 2015106/4 for 2007-08 Audi C6 S6 5.2 V10 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.
Problems and faults: Audi C6 S6
- 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).
- The air conditioning may not cool sufficiently and/or the outside temperature reading may be incorrect – this may be due to a poor crimp connection or defective outside temperature sensor.
- The coolant level warning light may illuminate in cold temperatures and then go off as the engine warms up – this may be due to a malfunctioning sensor in coolant reservoir.
- It may not be possible to remove the key from the ignition because the transmission selector fails to recognise that the transmission is in park – this requires replacement of the transmission shift selector.
- The remote central locking may sometimes not unlock the doors due to a problem with the door modules – this can be fixed by reprogramming the door modules.
- If the fuel gauge does not provide a full reading after re-fueling, the program for the instrument cluster may need to be updated.
- For some early models, the fuel door may not open because the release cable caused interference – the cable must be re-routed.
- The master power window switch may work intermittently due to interference with the trim.
