I just bought a 2001 audi s4. I pulled a p0300. So I did the timing, and am still getting the code. So I did a vag com scan and found out i have 0 spark and 0 compression on cylinders 1,2,3,and 5. Could that be the crankshaft position sensor, camshaft position sensors? I know with 0 compression it could and probably means bent valves, but I was just wondering if could be just the sensors?? Or is it a guarantee that the valves are bent, and possibly bad cylinder walls/cylinders? If I have to do the valves, then I may as well do a build now rather then later. Thanks for your answers. Also, does anybody know where I can get a ross-tech obd cord for cheep? Ross-tech only, no china knock off crap.

 

Zero compression wouldn't be related to anything electrical. And just to double check, you measured compression with a compression tester? (it sounds like you said you used VAG-COM to measure compression)

Personally I would spend time on diagnosing things mechanically. VAG-COM won't help here unfortunately.