2008 Audi A4 Problems: 3 Known Issues

On the 2002-2008 Audi A4, b6/B7 A4 owners who set P0322 almost always buy an engine speed sensor (G28) first, and a share of them are back on the forums a week later with the same code and the same no-start. The reason is that on this platform the failure is often the circuit rather than the pickup. The G28 lives at the bellhousing above the flywheel ring gear, and its lead runs up the back of the engine through a zone that sees exhaust heat, oil weepage and constant vibration from engine rock. Insulation hardens and chafes, a conductor breaks inside the loom, or the connector's female terminals spread and oxidise - and any of those gives the ECM the same result as a dead sensor: zero pulses, and P0322 stored as no signal. Ross-Tech's guidance for 16706/P0322 is explicitly to check the wiring to and from the sensor and the ECM before condemning the part, and at least one documented case traced the fault to a broken signal wire far from the sensor, up in the main loom near the ECU under the scuttle panel. Owners describe an engine that cranks at normal speed and never fires, sometimes preceded by weeks of hot-restart hesitation or a stall pulling into a parking space. Both the 1.8T and the 2.0T FSI are affected, and the code often shows up alongside P0321 (implausible/erratic signal) when the circuit is intermittently making contact rather than fully open - that pairing is a strong hint that the problem is a connection, not the sensor element. On the A4 there is also a purely mechanical version of the same complaint: a replacement sensor that is not pushed fully into its bore, or whose retaining bolt is left loose, sits at too large an air gap and reproduces the no-signal fault straight after the repair. What makes this pattern worth calling out separately is the money it wastes - the sensor is cheap, but diagnosis by parts substitution is not.

On the 2007-2016 Audi A4, audi TSB 2061604/5 applies to A4 2.0TFSI vehicles for model years 2007-2013 and 2015-2016 when the coolant-temperature warning is on or clear coolant marks are visible under the front of the vehicle or engine compartment, the leak can be reproduced, and pressure testing localizes it to the coolant pump or thermostat housing. The bulletin excludes model year 2014 and does not support 2017-2020, a universal failure mileage or a preventive replacement schedule.

On the 2002-2008 Audi A4, the multi-link front suspension used on B6/B7 A4 models is well known for premature wear of upper and lower control arm bushings/ball joints and, in many cases, outer tie-rod ends. Owners commonly report front-end clunking over bumps, looseness in steering, shimmy at highway speeds, and abnormal inner-edge tire wear. The issue is widely documented in owner forums and repair databases because multiple arms can wear at once, making the front end feel unstable even when alignment is repeatedly corrected.