This code could potentially be from cranking on the engine for a long time before it fires? Oil pressure builds to 40psi+ from cranking and N55 DME throws a code. This code happens to me frequently if I prime my car for too long with the Accusump before starting it. What does MHD say the actual oil pressure is? should be in the 14.xpsi range.
Do you mean the DME harness? If so, check the pins... might've bent some since I don't think the pin-out is the same on both of those harnesses. Then again, those codes are not on the same harness anyway lol
Check the ground strap on the rear of the engine?
1. Yeah, the client did crank the hell out of the engine when the harnesses were switched. How do we reset this? I did a fault delete and reset in MHD and unplugged both battery terminals in trunk and touched the two wires together for 30 seconds to dissipated, but the error comes back still...even when the car starts up instantly. So now I just picked up a new oil pressure sensor in case it got fried from the switched harnesses.
2. Yes, the harness first two cable groups got switched upon installation and then was corrected afterwards. Pins are straight like from the factory. Weird thing is, I and other people have made this mistake multiple times and the car runs perfect once we switch the harnesses to the correct spots...so this is a first for me.
However, there was an article from one of the forums that had a guy have the same error of the 2BF8 Rail pressure sensor permanently stuck - because he installed downpipes (like this car did) and then drove it around a long time without installing MHD to mitigate the catalytic converter absence. This client did drive the car for a couple of weeks after installing to the point that the SES light came on. That may be related...who knows.
3. I will check the ground strap again... I didn't even know there was a ground strap...where exactly is this strap? On the left or right side of the battery. I only know of the negative terminal that you take off and put on during sensitive electronic installs.
Thanks to all you guys who are chiming in. I appreciate it very much. I hope I can get this car into action again with all your help and a little luck.
VT