Hey TJers,
This is going to be a long post. After weeks now of trying to get my BEW TDI to start and stay running in my TJ Wrangler, I finally figured out all the issues I was having. Two were my own fault however the last issue was a wiring issue in the harness that I bought from Fast Forward.
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In last update, I had replaced my tandem pump that I messed up and had bought a copy of VCDS-Light so I could check a few things on the my BEW TDI ECU. Specially I wanted to see the fault codes and if the immobilizer had been disabled on my ECU, which it had been.
I was still getting a few fault codes however, one was about the N75 valve and the other for was the camshaft position sensor. At the time I didn't have the N75 plugged in but I had the camshaft position plugged into the harness. So to me the issue was a bad sensor, so I ordered a replacement and waited for it arrive.
Once the new sensor arrived, I replaced it but also noticed that I hadn't seated the injector harness plug into the head correctly, it was tilted slightly. That one was on me. However even after replacing the camshaft position sensor and getting the plug in the head seated corrected, I still couldn't get the engine to start though the BEW TDI was sounding better.
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At this point I reached out to a few different people online and I have to give a shout out to David Shoemaker. After several long conversations, he was able to help me figure out that the issue with my no start was the engine didn't know what position the camshaft was in, even though I had replaced the sensor.
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At this point David told me to start checking my wiring harness I got from Fast Forward. I pulled the wiring harness out of my TJ and with the wiring diagram that was supplied with the harness, I was able to figure out that one pin for the N75 value and one pin for the camshaft position sensor were reversed in the plug that connects to the TDI ECU. This should have been caught during the bench test when this harness was built.
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After taking apart the 60-pin ECU plug and installing the pins into the correct locations, I was finally able to get my BEW TDI to start and stay running. I just want to again thank everyone that helped me figure out this issue with the wiring harness, especially David. At this point I'm just grateful to finally be moving forward with my project and hopefully will have it done in the next few weeks.
Here is the video if you'd like to watch:
Thanks
Grant