Air bag igniter
Seat belt sensors
Info screen on dash
Wheel bearings (at least 8)
Control Arms
Oxygen Sensors
Windshield wiper linkage
And a million other things.
We have owned 7 Audi's in my family, including 4 A4's. This thing, actually all of them, are a money pits and cause a lot of wasted time at dealerships getting them fixed. Dealership service is terrible. I will NEVER buy an Audi again.
My 2000 Audi A4Q with over 100K miles has been outstanding on performance and maintenance. Original tires went 68,000 miles and still had more. No annoying electrical/mechanical or other issues just routine maintenance.
I bought a 2000 Audi A4 1.8t quattro with 90,000 miles on it for $11000.
After driving it for 2 days, a coil pack went out. After that, it has had no big problems so far.
The check engine light came on one time and went away, I bought it with a new turbo, new fuel pump, the timing belt was done, I have replaced wheel bearings, O2 sensor, all the vacuum lines, the turbo housing, the diverter valve (which is now atmospheric) brakes and rotors, tires.
It runs great for me; I love it and plan to keep it.
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