Bad idle

[defiant]

Good morning,I thought i would toss this out for you bronco gurus, 1989 with 5.8 motor. Dash light off, won't idle or idles fast--dash light comes on idles fine! Sounds backward to me! Maybe it is possessed! Thanks

 

[Rons beast]

Sounds like a vaccuum leak. The light may come on as a result of the computer making adjustments to compensate, then finding the inputs require adjustments outside the programed parameters.

Pull the code/codes to get a better idea what to look for.

Take a good look at all vaccuum lines and connections.

 

[defiant]

I replaced all vac lines ( they were shot) I will pull codes after turkey day! And i will check for gaskit leaks! Thanks for info. I'll let you know what i find!