Im having a problem with my 90 tsi awd, its got a new rebuilt motor in it and the caps have been replaced like last month. After the rebuild the motor would start but sputter out of the exhaust, so we had the ecu caps replaced. And now the car will not even start. We have fuel, but no spark. The timing marks are all aligned. We have replaced the power transistor unit and also the coil pack, but we have no spark still. The mpi fuse checks out good also, we do not have a clue on what to check next. When we plug in the pocketlogger, it says ECU COMM error, dunno if that could be it. The crank angle sensor used to have to be turned all the way advanced to get the car to run, but now of course the car wont start, so can a bad CAS cause no spark? I am lost, help me!

CAS does control spark, yes. I believe it does control fuel as well so it may or may not be the problem your having. I'd start with the ECU and then look towards the CAS.

The crank angle sensor has a different error code. Could still be the CAS but my money is on the ECU. Sometimes if the caps weren't replaced timely enough the electrolytic fluid will eat through some of the circuits...

Also, and I'm not trying to step on toes here, there could be the chance of damaging something else on the ECU when you swapped out the caps. It's easy to overheat a component on a circuit board with a soldering iron. But as Nate said, its more than likely the fliud from the caps.

damn i wish i was located more towards you guys im in mattoon, which its tough to find others with a 90 turbo around here, i will see what i can find though, thanks a ton