I finally tested TPS voltage, and think its not set correctly. come and see

[charlesw6954]

this is how i tested it. i turned the key to the on position and tested the voltage by red to green and black to black (right???). i got .83 or .87.

did i test it right? am i suppose to have the engine on? i dont think so.

oh yea at idle it jumps from 500 - 1000 so yea its gotta be off.

 

[Black 93 Fox]

Have you checked for vac leaks they can also cause bad idle's? I know mine is off my car idles at 1000to1200 I havent got around to setting my TPS

 

[charlesw6954]

man when i had that problem with the stang i looked thru out the engine bay saw 2 vacuum hoses just off and leaking i guess so i taped em up. other than that there are no vacuum leaks. as i know of. but i just bought this tps sensor new from autozone so it could be off.

i think the vacuum hoses that were off were probally for the smog that i took off and yea. they are next to the firewall by the air conditioner tank thingie.

 

[Black 93 Fox]

man when i had that problem with the stang i looked thru out the engine bay saw 2 vacuum hoses just off and leaking i guess so i taped em up. other than that there are no vacuum leaks. as i know of. but i just bought this tps sensor new from autozone so it could be off.

i think the vacuum hoses that were off were probally for the smog that i took off and yea. they are next to the firewall by the air conditioner tank thingie.

LMAO I did the excact same thign. the two small hose's that run to the two sensors for the smog line i left them open like you. thats what started my whole idle problem. I pluged thoes then turn my idle screw to get my idle down got it down to 800 but then the damn gas pedal gets stuck closed so i had to screw it back open some more so now it idles at 1200 or 1000. Plus my tps is way off. I said screw it just gona have the shop do it.

 

[jerry beach]

Give more details of your problem. You have pulled the codes, correct? Tell of any codes you have not resolved. Not all of them matter, mine throws a few and runs right, just emissions stuff, and it gets great mpg.

If you just have a rolling idle, have you cleaned the TB and MAF? I think you have done these things. Do yourself a favor and get the Probst book, or the Watson book if you can find it. Well worth it, they give step by step instructions to troubleshoot your problem. I dont have the patience to type that stuff in, and dont have a scanner, but these books are very helpful.

Have you tried the 10-pins too? I did them in my car and it made no difference. Is your TB sticking at all?

 

[MustangMulch]

I was having the same idle problem a while back, with occasional stalling on the cold mornings. I tested my TPS voltage and it was pretty low. I think the ideal reading with the engine on is .97-.99. I just twisted it and got it up to .97, and the idling problem was history.

 

[TheUser]

by the way the Probst book Jerry Beach spoke of is "How to Understand, Service and Modify Ford Fuel Injection & Electronic Engine Control" by Charles O. Probst, SAE. I picked mine up at the local Barnes & Noble for $30 after Michael Yount mentioned it a few days ago. I can't wait to read it and it does have the troubleshooting stuff will be nice to have as well.

 

[1hot5.0]

Yes, the correct tps voltage setting is .97 volts. You test it with the key on, engine off. As far as vacuum hoses go, I had a leak at the back of the upper intake manifole, and it was causing some rough idle problems. You may want to check there just to be sure there is no leaks. Also try leaning the mass air like Jerry Beach has recommended.

 

[charlesw6954]

you mean clean the maf?? no my tb doesnt stick