Raised Idle, still think IAC?

[Magicfan25]

Ok, I posted the other day about the Rough idle at first start up (title was something about 98 SOHC rouch idle at first start, if ya wanna glance at it too). i havent had a rough idle since then, but now whenever I start it the idle sits at 1000RPMs, regardless if I stab the gass a few times or whatever. Once i put it in gear and drive off from wherever the idle will be fine from then on. The raised idle occurs at ALL starts now, but the rough idle hasnt happened again...Does this still sound like a dirty/bad IAC? i think I'm just gonna take an hour and clean the MAS sensor (from the tips section), clean the TB and IAC..Maybe there will be a new car under the tree in the morning. Then I can flip this thing the bird, tell it to go to hell and not worry about it <ok,I'm done ranting>. Merry Christmas everyone

 

[MSTNGGUY88]

I'm not sure if this applies to the fuel injected but on the TBI's there is an electronic diapraghm controlled choke that will cause that. Just a hint but not real sure if it applies or will help. Maybe someone else that reads this can inform a little better about it.

 

[jimmiecakes]

Yep, the IAC could result in a high idle. Couple of other things could be vacuum leak or TPS. Since you've made a change in the way the IAC reacts mechanically to the signal from the ECM, you could give it (the ECM) a couple more days to relearn stuff or disconnect the battery cables, touch them together for a few seconds and then go for a drive.

If the problem persists after that, then post again to the forum.

Merry Xmas

 

[Robert]

Does the idle drop to normal levels after the engine warms up? If yes, then it is normal. The engine should run about 1000 RPM until it gets up to operating temperature. My '97 first idles around 1000 RPM when it is below about 55 degrees outside. Once I have driven a couple of miles, the idle drops back down to around 600 RPM. If your idle doesn't drop to 600 RPM after a few miles, then a bad or sticking IAC can cause it.