OBD2 S52 Dies when driving forward

[AndrewK]

After almost a year of flawless performance my S52 swap is now giving me serious issues. It will start fine, idle fine, reverse fine, but as soon as I drive forward it dies. Then it won't restart for a while.

Peake reader shows no codes other than the one I already know about (32 EVAP system running losses valve - because I'm not using an OBD2 FPR). The first few times this happened, I got it running after I reset the CEL. I'm now thinking that was just a fluke.

It has to be a clue that every time it happens when driving forwards. Wheel speed sensor issue? ECU issue?

[DesertBMW]

It is not the ECU because ECU gets the same speed signal when going into reverse. To me sounds like bad ground wire, or some other wire that is rubbing against something and got worn out over time. Puting it in reverse makes the engine tilt other way

[AndrewK]

You might have hit the nail on the head. Or at least I hope so.

Late last night I found the power wire to unloader relay terminal 15 was a little loose where it bolts into the power junction on the firewall. That relay powers the coils.

I hope that fixed it, but I have my doubts. Going to take her on a test drive now.