2004 Audi A6 Quattro Repair and Maintenance

A guide to problems, costs, maintenance and repair for your 2004 Audi A6 Quattro

2004 Audi A6 Quattro Problems

Overheating Due to Failing Thermostat

The thermostat may erratically stick open or closed. The can result in illumination of the Check Engine Light and/or engine overheating.

Flasher Relay Failure Can Cause Erratic Turn Signal Operation

Erratic turn signal operation can be a result of a failing turn signal flasher relay which will require replacement.

Check Engine Light Due to Vacuum Leaks, Oxygen Sensor, or Catalytic Converter Fault

Vacuum leaks, oxygen sensor failure, and catalytic converter efficiency faults can cause the Check Engine Light to illuminate.

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2004 Audi A6 Quattro Questions

My car blew a water hose and automatically shut down. now it won't start. (1 answer)

While driving the low oil light came on. And then the hose blew. The car shut down and after filling it with oil and repairing the hose, now the car won't start. Not even turn over. The EPC light is on as well.

Problem with driver rear shock vehicle sways erratic when hit bump, sharp turns (1 answer)

When driving and take sharp turn rear drivers side sways

transmission with Battery removed I can shift, with battery in I can't (1 answer)

My car was diagnosed with a bad brake switch the car drive anyway and then had an accident not related at all.. but the damage was to the under carriage oil pan area and since then my shifter will not move from park with battery connected with battery remove the shifter works fine So I think the ...

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2004 Audi A6 Quattro Reviews

Some plastic fittings on the front passenger seat have failed. Several painted surfaces on the headlight switch, mirror switch and heating and A/C controls have worn off. The radio on/off button has come off. The front suspension needs relatively frequent repairs. The roads are terrible around here. Water pump and oil cooler replace at different times. The latter repair VERY expensive.
i love my a6

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