Hi there, I'm new at the forum ..... I've an strange problem on my 2001 jetta AEG 2.0 .... it cranks but won't start.


Issue 1:


I know the car won't start on key ON (2 position) because the Check Engine Light is OFF (all other lights show on normally, immo also checked) and also no fuel pump priming. And when CEL is off (KEY ON) sometimes from one moment to another, the CEL goes ON, I can hear the fuel pump priming and stays on until it cranks and starts normally ....




Was scanned by a friend with vcds and the code registered in instruments is: no communications with ECM - intermittent.


No other codes, checked battery, alternator, every ground, fuses,.....


Sometimes the CEL is on (starts) and sometimes not..... this can be a faulty fuel pump relay?????




Issue 2:
Crankshaft position sensor. When I'm driving like at 40kph or 60kph (no rpm redline NEVER), sometimes in idle!, CEL comes on and power is reduced like a crash ..... Code registered: engine speed exceeded - warranty VOID.
So maybe I think it was a bad CPS. Putted a new bosch and after a few days, the same problem. So I've swapped my CPS with a friend and the same symptom in my car. My friend's car runs normally with my sensor.




This 2 sympstoms can be related too and what may I check?




Thanks a lot !!!!
Best regards

Thanks a lot!!!