foopy

did someone say weight reduction? GO FOR IT!

johnkean

I am actually working on this issue as we speak. I bought a 91 Vert and when I first started it and warmed it up it was nearly perfect at about 800 rpm idle. Then after driving it a few times the idle strated doing the same thing as you describe. It would jump up to like 1200 to 2000 rpm, bounce up and down, you could even smell that the mixture was getting richer. I have checked the voltage on the Green/Red wire on the tps when warm to make sure it is at 1.00 volt and still see the problem. I did order a new tps but if that does not solve the issue I am thinking it could be the ecu not working correctly. If the ECU has an intermittent electrical issue then this would make since why my idle probelm would come and go. One method is to check the actual voltage on the green/red wire on the ECU itself which should be at 1.00v. But I am leaning toward a bad ECU or TPS in your case also if you have already ruled out the TPS is adjusted correctly.