High RPM Stumble/Cutoff - Running out of Ideas

[JIMBOkye]

UPDATE:
played with CPS gap, no change.

BUT, as I raced it around the neighborhood it starting throwing a check engine light as I hit the stumble point, and also when quickly letting off the throttle, or "bliping" for downshifts.

So I stomp tested it and it came up with a 1261 code. This is "fuel pump relay" code.

So I swapped the DME relay, no change, swapped the fuel pump relay, no change. I guess I'll have to dig into the wiring harness to see what is going on.

I'll confirm the wiring to the 2 relays. The way I understand it, the DME switches on the fuel pump relay by internally enabling ground to complete the fuel pump relay circuit. Any thing I'm missing here? or other thoughts?

Not sure why this check engine light just started coming on, and was not before.

[paynemw]

I talked to an older BMW mechanic yesterday. He said that the C191 plug needs to be crimped. So you have a male plug that slides into a female sleeve on one side of that C191 connection. Apparently that connection needs to be tightened to ensure proper connectivity. The mechanic said they'd slide a drill bit into the female sleeve, if it didn't stay in there, they would just make sure it was tight. Apparently that was a fix for a huge idle problem.

[JIMBOkye]

Update: Formally giving up. Bought a megasquirt and will be doing a wasted spark type setup with e36 TPS, wide band O2, MAP and MAT, AFM delete.

[Kershaw]

There ya go.