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Audi A6 Quattro Problems

Check Engine Light Due to Vacuum Leaks, Oxygen Sensor, or Catalytic Converter Fault on Audi A6 Quattro

Problem Description and Possible Solution

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

(37 people reported this problem)

Audi A6 Quattro Vehicles With This Problem

RepairPal Fair Price Estimate
$655-$3077
RepairPal Verified
Average mileage: 117,368 (10,900–200,000)
Exhaust & Emissions affected: 2.7L V6 Turbo
5 model years affected: 2000, 2001, 2002, 2003, more2004
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Brake problem? Or maybe a faulty head gasket cylinder?
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Viewing 1-10 of 10 comments
My check egine light is back on only two days after a tune up correcting missfire i dont have the funds to replace either catalytic converter or O2 sensor at this time but this is what the code is fuel too rich watever that means.
Have been told that it is the O2 sensor. I have had them replaced and the CEL is back after 10k miles.
Car looses power, then surges all of a sudden, then act like it wants to shut off. Fumes coming into drivers area bad enough to burn mu eyes.
CEL on. Checked OBDCOM--diagnoses was improper Catalytic converter air mixture coming from back O2 Sensors. Will replace catalytic converters and O2 sensors.