Recalls & faults: Audi D3 A8 (2003-10)

Recalls: Audi D3 A8

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 D3 A8

• In February 2006, a recall was issued for Audi D3 A8 vehicles fitted with the optional Michelin Pilot Sport 255/35 R207 97Y tyres due to a potential sudden loss of pressure (PRA 2006/8309).
• In December 2006, a recall was issued for Audi D3 A8 vehicles due to isolated cases in which the driver’s airbag may not deploy as intended if triggered in an accident (PRA 2006/8928).
• In July 2016, a recall was issued for Audi D3/4E A8 vehicles that had solar sunroofs and were manufactured from April 2007 to June 2008. In these vehicles, the glass panel may not have been sufficiently bonded to the sliding roof frame because the bonding surfaces were not clean during the production process. If the glass panel became loose when the vehicle was moving, it could pose a danger to other road users (PRA 2016/15511).

Problems and faults: Audi D3 A8

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 A8 V6 diesel engine: NOx emissions “defeat device”

Audi D3 A8 vehicles powered by 3.0-litre diesel V6 engines (engine code: ASB) that were available for sale from 2009 to 2010 have software in the electronic control module (ECM) that can sense – via sensors measuring the position of the steering wheel, vehicle speed, the duration of the engine’s operation and barometric pressure – when the vehicle is undergoing emissions testing. The ECM then operates in a low NOx “temperature conditioning” mode to satisfy emissions standards.

At exactly one second after the completion of the initial phases of the standard test procedure, the software immediately switches to a “normal mode” and changes a number of operating parameters that increased NOx emissions. In other tests where the vehicle did not experience driving conditions similar to the start of the emissions testing procedure, the emissions were higher from the start, consistent with the operation and existence of a “normal mode”.

The software on these vehicles constitutes a “defeat device” since it is an Auxiliary Emissions Control Device (AECD) designed to circumvent emissions testing. Volkswagen has admitted that all its 3.0-litre turbo-diesel engines from ‘model years’ 2009 through to 2016 have defeat devices.

Carbon deposits (build-up) on intake valves

Audi’s naturally aspirated, direct injected petrol engines (such as the D3 A8’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:

1. the vaporisation of oil which is not trapped by the oil separator; or
2. 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 D3 A8 4.2 FSI: low-pressure fuel system sensor

In March 2008, Audi issued technical service bulletin 2015106/4 for 2007-08 Audi D3 A8 4.2 V8 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 D3 A8 quattro: noise when shifting to/from fourth gear

In December 2006, Audi issued technical service bulletin 2013023/1 for 2004-06 Audi D3 A8 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 D3 A8 quattro: whining noise on deceleration

In June 2008, Audi issued technical service bulletin 2017932/1 for 2004-07 Audi D3 A8 quattro vehicles because a whining noise may be heard in deceleration from freeway speeds. According to the service bulletin, the whining noise was due to wear of the bearing and bearing carrier in the rear differential housing. To fix, the 01R final drive (which had a black housing) was to be replaced by the new 0AR final drive (unpainted and therefore silver in colour).

The 0AR final drive was introduced during MY 06-07 production for individual engine-gearbox variants.

Audi D3 A8 4.2 V8 and 6.0 W12: misfires and ignition coils

In December 2006, Audi issued technical service bulletin 2013623/1 for 2005-06 Audi D3 A8 vehicles with 4.2 V8 or 6.0 W12 engines and VINs in the range 4E 5N 007600 to 4E 6N 025500. 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 D3 A8

• Squealing and/or chirping noises from the serpentine drive belt may be attributable to a damaged upper idler pulley that requires replacement.
• The anti-lock braking system (ABS) may activate unnecessarily under normal to light braking pressure due to cracks in the tone wheels.
• The air conditioning may not cool sufficiently and/or the outside temperature reading may be incorrect due to a poor crimp connection or defective outside temperature sensor.
• For models with the 4.2-litre V8 petrol engine, poor performance accompanied by a hissing sound may be due to a vacuum leak at the intake manifold – this may require re-tightening the bolts, replacing the gasket or replacing the gasket and applying sealer around the intake ports.
• The power steering may be noisy and feel like it is skipping – in the absence of leaks, the power steering reservoir or pump may require replacement.
• The automatic leveling suspension system may stop working due to problems with the sensors – the sensors may need to be replaced if they were of an earlier design; the updated sensors can be identified by a black dot.