It looks like I'm not out of the woods afterall. 86 8 valve n/a
It got cold again this week, and the car started to act up.
Here is the latest observations:
The car starts and runs normal. It drives normal in all gears...just not over 2000rpm. Even in 5th gear At 1500rpm, if I floor the gas pedal, the car pulls well right up to 2000rpm. If i keep it floored, the car will not accelerate, and will actually slow down until it gets below 2000rpm and then accelerates back to 2000rpm.
In Neutral, the car will rev to 2000rpm. No matter how hard I push the gas pedal, it revs to 2000rpm then osilates from 2000-2500rpm and won't stop osilating unless I release the throttle.

This is what has been done in the last 3 weeks:
New reference and speed sensors
New tps
New spark plugs, wires, cap and rotor
New fuel filter
Injectors sent for cleaning/calibration
New cat and exhaust (last year

I have verified that the fuel pressure is good while it is running, and stays ok even as the rpms osillate when the throttle is pushed beyond 2000rpm.
I have a rogue n/a tune installed, and I even put the stock ecu and afm back in and it still won't go beyond 2000rpm.

It acted up when it was -30 outside, and yet worked fine the next day when it warmed up outside. (I drove no problem past 5000rpm) The next day again, it would not rev beyond 2k.
It has been somewhat intermittant, in that I was able to drive the car in a snow storm with zero driveability issues, only to have it act up the next morning. I am not driving the car to work at this time until I can sort it out.
Any ideas?

 

May be a bad connector for a speed reference sensor? That's what was wrong with my way. Not sure exactly how to check that. That's what my guy figured out that was wrong.

 

The problem is still the same as last time... TPS and/or TPS wiring.
Since you replaced the TPS, most likely the issue is with the wiring.

 

Bad DME relay?..

 

see if you can figure out if it's ignition or injectors - put a light on each and watch

 

Borrow a timing light and see if and where you're losing fire.

 

Darn tps wires are all buried under the manifold, but I will try and trace the wires back.

I have a timing light, and I haven't tried it again. I used it to trace a stumbling idle which turned out to be a clogged injector (hence the injectors removed for servicing). It is easy to try again and see what happens, though I think I have that system running pretty good now.

I really dislike intermittant issues.
As many know, this car is a daily driver. It has now been moved to a weekend only car, as this last episode has caused me to rent a car twice while it was in the shop, and now again as it is trapped at home. I picked up an E46 on the weekend to resume daily duties. A shame really, as the 44 was doing quite well and was in its 3rd winter as my full time DD.

 

I don't know if this will help but...
I was losing fire on 2 and 4 above 4800. I mean nothing.
Took it to the shop and they tested it with a known good DME and didn't fix the problem.
Then the tech was messing with teh SR sensors and disconnected one while the car was running and it died. I guess that with a pair of them it should continue to run even with one dissconnected? Not real clear on that.
Then he pulled back the rubber boot on the SR plug and sure enough there was a broken wire.