I've got an issue I've been working on on the Tbird for the entire time I've had the car; and I know it's a wiring issue somewhere.
I've swapped a bunch of stuff, but can't find it.
I have all the drawings, datalogging, electronic skills, everything I should need.
The problem is it runs rough sometimes at low end, until it warms up, or always Sometimes in the rain.
Here's what I've swapped:
EEC, Coil Packs, Plugs and wires, Wiring pigtail to EEC from under the hood, wiring pigtail to transmission, O2 sensors (all).
Probably more stuff I'm not remembering right now.
It does not show in a datalog as anything other than missing on random cylinders.
I can see when it commands 2nd gear; but I don't see any sensor changes that would cause it.
The weirdest part is that it will occasionally throw the tranny back into second, commanded by the eec, even at 70+mph. That's fun.
I've swapped the eec with a good one from another running car; still does it in the wet. Occasionally.
It did this with the original EEC, that eec went bad with another tranny related problem, which was fixed with a new EEC.
I have tried other EEC's same problem, and this problem doesn't occur with those EECs in another car.
I thought I had finally found it with water in the plug wells, but it recurred after the last rain, and there's no water in the plug wells.
The car runs Great 99% of the time, which is the thing that makes it hard to find.
Suggestions for additional things to datalog, things to check, voodoo rituals to perform; all useful suggestions are welcome.
I've swapped a bunch of stuff, but can't find it.
I have all the drawings, datalogging, electronic skills, everything I should need.
The problem is it runs rough sometimes at low end, until it warms up, or always Sometimes in the rain.
Here's what I've swapped:
EEC, Coil Packs, Plugs and wires, Wiring pigtail to EEC from under the hood, wiring pigtail to transmission, O2 sensors (all).
Probably more stuff I'm not remembering right now.
It does not show in a datalog as anything other than missing on random cylinders.
I can see when it commands 2nd gear; but I don't see any sensor changes that would cause it.
The weirdest part is that it will occasionally throw the tranny back into second, commanded by the eec, even at 70+mph. That's fun.
I've swapped the eec with a good one from another running car; still does it in the wet. Occasionally.
It did this with the original EEC, that eec went bad with another tranny related problem, which was fixed with a new EEC.
I have tried other EEC's same problem, and this problem doesn't occur with those EECs in another car.
I thought I had finally found it with water in the plug wells, but it recurred after the last rain, and there's no water in the plug wells.
The car runs Great 99% of the time, which is the thing that makes it hard to find.
Suggestions for additional things to datalog, things to check, voodoo rituals to perform; all useful suggestions are welcome.