Idle Air Control Valve

Did you spray cleaner in the IAC opening in the throttle body? The plunger may be hanging up on residual gunk.

Also check every vacuum hose for leaks. Spray carb cleaner on the hoses and connection to see if the RPM change when you spray over a leak. make sure you didn't lose the o-ring on the IAC and the gasket is good.
 
Did you spray cleaner in the IAC opening in the throttle body? The plunger may be hanging up on residual gunk.

Also check every vacuum hose for leaks. Spray carb cleaner on the hoses and connection to see if the RPM change when you spray over a leak. make sure you didn't lose the o-ring on the IAC and the gasket is good.
I didn't spray anything. Just pulled old sensor off and put new one on. O-ring is in place. The new sensor didn't come with a gasket, just the o-ring. Maybe it isn't tighten down enough? Probably just pull off the throttle body and clean it all out. The IAC was pretty filthy so I imagine the rest of it is as well. I can replace the TPS at the same time. Fingers crossed.
 
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There's a big opening you'll see in side of the throat of the throttle body that goes to the IAC plunger. I's spray a bunch of cleaner in there too on the chance the plunger is hanging up. Sometime over tightening can make it worse like the valve cover. The o-ring should work ok. I'd spray everything clean inside the throttle body.
 
Check out my recent thread my " TPS issues" on my 91 4 cyl which included new TPS ,IAC's and a TB cleaning. Ive read endless posts on several forums and the same seems to hold true in 90% of the cases. However In your case Id start by disconnecting the neg battery cable and let it sit for a hour or two, some also turn on the headlight switch for a few mins to kill any parasitic voltage left to clear the PCM memory. That seems to be the trick to where to start. Eventually the PCM will "adjust" to the correct idle speed. That's the theory as i read, my 91 still idles at 1100+ rpm from a pre replacement of parts when the idle was around 500. If you pull the IAC again look closely at the tip and you should be able to see if it appears if the pintle is seating 100% or its not due to carbon build up in the TB seat. Id love to know why when you replace the TBS the idle high idle issues begin. Ive yet to find any answer from the majority of the posts related to this.
 
OK Finally had a chance to work on this. I pulled the throttle body off and the IAC sensor and cleaned it all down which is very much needed. I took the battery cables off the battery while I did all this per recommendations. Put everything back on and it seemed to work. It is idling around 800 now. I still cannot get the TBS off to replace so I will have to sort that out. But, big improvement. Thanks.
 
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FYI when i decided it would be a good idea to replace my TPS I could not get the torx screws loose and destroyed the heads of the screws. I had to remove the TB and carefully grind off the heads to where I could slip off the TPS leaving a 1/4" or so of stud left screwed into the TB. Then I soaked with release agent and worked whats left of the screws back and forth very little at a time with vise grips until they came out. I Was pretty sure they were gonna snap off flush with the TB edge so be gentle. Yes, they are locktited in by the factory.
 
FYI when i decided it would be a good idea to replace my TPS I could not get the torx screws loose and destroyed the heads of the screws. I had to remove the TB and carefully grind off the heads to where I could slip off the TPS leaving a 1/4" or so of stud left screwed into the TB. Then I soaked with release agent and worked whats left of the screws back and forth very little at a time with vise grips until they came out. I Was pretty sure they were gonna snap off flush with the TB edge so be gentle. Yes, they are locktited in by the factory.
Thats really helpful. I tried taking mine off and one of the screws sheared off and some is left in the TB. I will follow your lead above and try that method to release the busted screw. Did you have to just pry the TBS off and then get the screw out? I'm having annoying high idle issues and replacing things one bt one to track the cause down. Sura permanently at 1400rpm even when fully warm. Grrrr!
 
IF IT hAS Thread locker, use heat. (small torch) gently and it gets soft and comes off. (the red locker is 300f to 500f spec, in the data sheet of it)
the sizes are all here, what heads you have now is anyones guess, mine are torx. T20.
thread locker is so the maker does not get sued for $1billion dollars like toyota was , falls off and leaks and RPM at 3000 all the time and grandma runs over kids, see? Torx also assembles faster in the factory, Phillips stink, I like hex Allen too, an are all sold every one at boltdept dot com.
I have full set of screw pitch gauges,. so know what there , here is my results.
note the metric part mix.
how is this. guess 91 to 95 same, me. (SBEC PCM), do not use Red Loctite, it is too extreme for here. the engine does vibrate so...
this is my replacement TB, mine the bottom 10-24 hole stripped out (PO done)
not sure me if m5 tap drill will clean up the damage., i bet not
helicoil? 10-24 uses
13/64" TAP
drill (0.203) , i think will fail due to thin margins

the 4 screws at near top yellow arrow are security keyed.
1995-screws.jpg

the fender bolt head here is a joke, I have huge boxs of bolts/screws here. to test. this was first grab. fits, all these are sold at the big box stores, hardware in the bolt department. under SAE machine screws. , the TPS comes new with screws and so does IAC Im told.
use heat do not break off such tender screws. The body is only aluminum do not over torque them.

m6 are 9ft/lbs only , x12 is 108inch/lbs do not strip them out
#10 or set gently tight, hand tight and 1/4" turn more,max
the TPS can be put on wrong if the tangs not aligned. The TPS must advance full range, TV from 0 to 100% throttle. the FSM shows how and is free.
above MPI not TBI.

tangs.JPG
 
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