Idle issues
 

i have a 87 truck that i took the whole 89 4runner harrness out of the truck is ideling up and dwn spartically i think it is the brain but i am not sure any ideas also i think it is idleing to high please help

Moved the post to it's own thread...

Does it idle up and down all the time or only when the brake pedal is pressed? You said it seems to be idling higher than it should be, if so then it'll idle up and down when the brake pedal is pressed. Get it back to a proper idle and the up and down issue should stop.

I just fixed an idle issue with my truck, check out my thread, maybe it will help you out....

https://www.yotatech.com/forums/f120.../#post51746211

Oh and when I was reinstalling my TB, I hooked the TPS up wrong and it almost violently would idle up and down the second I started it without pressing the brakes this time, luckily I noticed it and 10 minutes later it was fixed and ran perfect, just an idea and something to check