pcarfan944

Thanks for the leads, I’ve got a few places to start now. It might be worth mentioning that lately when the engine is cold, it kind of bucks and shudders with a low idle of about 500rpm for about the first 30 seconds of operation, after that it smooths out and runs fine. Is that a signal that it’s not getting enough fuel or something? Might be a clue for you experts.

thanks!

RedlineMan

Heckydurn!

That little explanation strengthens my feeling that something is telling the DME that the car is warmer than it really is when cold. When it actually does warm up a little, the culprit is back to proper resistance levels. I'm talking head temp sender here!

Sounds like you might be wise to just check the Big 5 of Bosch driveability: TPS, HeadTemp, AFM, O2, Crank Sensors. Might as well know what the resistance of all the assemblies is. Worst case is you will have to wait for it to get worse before it really shows up.

gtroth

There's guessing and then there's measuring. Measure the damn fuel pressure with the DME relay removed and the pins jumpered. Then measure it running with the relay back in place. Then see how long it holds pressure after shutting it off. While you're at it maybe measure the fuel delivery rate. Then you'll know. If you're wondering about temperatures reading improperly, measure the resistances of the thermistors at the DME connector. Same story with TPS. For the AFM, measure the voltage vs. angle right at the AFM connector (a bit harder since you'll need to jumper the supply volatage from the removed connector back to the AFM). Basically, follow the DME Diagnosis Procedure in the FSM. Believe me it's alot more fun than guessing and swapping out parts. And you'll be surprised how much confidence you'll gain when you see how much is correct.

Bit of a rant - sorry (long day).