2002 VW JETTA AVH 2.0

Hi Group,

Originally towed into the shop for a clutch problem. When we started it up it had a long cranking time or started and died a few times before it ran.

I scanned it and there was a camshaft position sensor code. We went forward with the clutch job and also replaced the cam sensor (I did this job and double checked the timing, it is ok). When the clutch was finished it was started up and ran very poorly (misfiring). It was determined that the main ground cable to the top bolt on the transmission was left off (we had the apprentice doing this job).

The ground was reattached and the codes cleared, but the car still missed. I determined that the main positive cable to the starter was not tightened either. I tightened it, but it still missed. I tried a hard battery reset and throttle adaption but it still misses.

I have codes P0300, P0301, and P0304. After checking the spark plugs for cylinders 1 and 4 something didn't seem right. I remembered an old bulletin talking about improper cylinder identification on AVH engine and sure enough it applied. My misfires are from cylinder 2 and 3.

To confirm that the new cam sensor was not the cause I installed the old cam sensor (Bad, later determined no signal from sensor). Now the car runs on all cylinders and idles, no misfires.So the new cam sensor caused the problem. I would like to point out that there was NO cam sensor code with the new sensor. I installed a dealer cam sensor.

I am back to the original problem, the car sets 17746 - Camshaft Position Sensor (G40) P1338 - 35-00 - Open or Short to Plus. If I clear the code and start the car the code comes back immediately. It also cranks too long before starting and doesn't take the accelerator when trying to drive it.

I think what is happening is that when the cam sensor is not working I am put into a limp home mode, probably running off a map and not the cam sensor signal. When I have a working signal coming from the sensor that is when all the misfiring starts.

Is it possible that the circuit that processes the cam signal internally is damaged from the starting the car with no ground attached? Or is this far fetched?

My biggest concern is that the engine control unit was damaged by starting the car with NO ground strap to the transmission and/or the loose main positive cable to the starter.

Thanks for any help or advice, Shep

VIN: 3VWSK69M32M140939 Mileage: 264130km-164122miles
Address 01: Engine Labels: 06A-906-032-AVH.lbl
Part No: 06A 906 032 FQ
Component: 2.0l R4/2V G01 4069
Coding: 00001
Shop #: WSC 26149
VCID: 72E048E43EA63DAE77-5120
3VWSK69M32M140939 VWZ7Z0A4328961

3 Faults Found:
16684 - Random/Multiple Cylinder Misfire Detected
P0300 - 35-00 -
16685 - Cylinder 1
P0301 - 35-00 - Misfire Detected
16688 - Cylinder 4
P0304 - 35-00 - Misfire Detected
Readiness: 0110 1101

****ORIGINAL CODE NO LONGER PRESENT**** (when new sensor is installed and misfiring)

17746 - Camshaft Position Sensor (G40)

P1338 - 35-00 - Open or Short to Plus