So I am fairly new to any German engineering but very capable and willing to learn. I found a nice Quattro for a low price thinking it would be a nice investment if I could diagnose and repair it. So I found a craigslist add in my area and scooped it up. The guy selling it said there was major engine problems, something like cylinder 2 had zero compression and it was idling roungh and misfiring.

What I came to find out after getting it home, I ran the VAGCOM and cleared the old codes. Ran it again, and the codes just said Misfire detected, Throttle position too high,

17953 - Throttle Valve Controller: Malfunction P1545 - 35-00 - -
16507 - Throttle Position Sensor (G69): Signal too High P0123 - 35-00 - -
18264 - Throttle Potentiometer (G69): Error Message from ECU P1856 - 35-00
17708 - Misfire Detected. Probably Reason: Low Fuel P1300 - 35-00 - -

It didn't say anything about compression or even which cylinder is misfiring. I am crossing my fingers this engine is fine. Change the fuel filter, replace or flush the injectors, replace the throttle position sensor... any other ideas?

 

FYI - the VAGCOM isn't going to tell you about low compression in a cylinder. The only way to do that is with a compression tester. Might want to start there before you possibly waste money on new sensors and tuneup parts. If it has a dead cylinder there is no point on going any farther. But u might get lucky and the guy had no clue what he was talking about!

 

Based of the codes and what information the seller told you, i would check fuel pressure and compression check the engine to get a good idea what's going on in there.

 

run a throttle calibration procedure and see what happens.