5.0L high idle

[Killa]

1995 mustang gt 5.0L automatic, car is high idle as 2k rmp and hang their, unplug MAF idle drop down perfectly but some time it back up to 2k and drop down 800rmp. While I unplug MAF it drive fine, but some time it idle spike again.

Here what I already do, no vacuum leak, clean and reinstall IAC, and replace the MAF sensor. Now either IAC or TPS is bad, I dont know how to pull code on this OBD I. Should I buy both IAC and TPS to try out see which one is bad ? thanks

 

[Killa]

unplug MAF, car idle around 800-900 rmp, plug it back in and it spike to 2k rmp.

 

[jrichker]

See the "Surging Idle Checklist” for help with all your idle/stall problems. You can guess at the problem and throw parts at it, or you can use the checklist to help you find the problem quickly and inexpensively. It’s free and doesn’t cost anything: at last count there were more than 103,000 visits and still climbing

The quick and easy way to dump the codes is in there too, and all you need to do it is a paper clip! The first two posts contain all the fixes & updates. At last count there were 24 possible causes and fixes for surging idle/stall problems. I continue to update it as more people post fixes or ask questions.

 

[Killa]

just to be sure, when you say " surging idle " my never die on me, but when i turn it on, it spike at 2000rpm and stay their and not going back down, is that still caller surging idle ? because when I did a surging idle term, it look like rpm jump up and down, mine is stay at 2k rpm. thanks

 

[foxbodymike87]

lower the idle screw or adjust yout TPS sensor

 

[jrichker]

just to be sure, when you say " surging idle " my never die on me, but when i turn it on, it spike at 2000rpm and stay their and not going back down, is that still caller surging idle ? because when I did a surging idle term, it look like rpm jump up and down, mine is stay at 2k rpm. thanks

Read the "Surging Idle Checklist” It covers all types of idle problems. . It won't take more than 10 minutes and may provide you with the information you need to find and fix the problem.

 

[OonDeanisS]

try unplugging the IAC, that fixed my high idle. i dont know what harm it could cause though, if any.

 

[HISSIN50]

Please also list any pertinent modifications (things like an open air-filter element in the engine bay are important).

 

[Killa]

i forgot to update , i put in new IAC and it fix the idle. car run good . and no jerking back and forth. and alot quiet now.