1992 High Idle question - IAC? throttle cable too tight?
06-28-2005, 10:20 PM
#1
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1992 High Idle question - IAC? throttle cable too tight?
someone mentioned that my throttle cable might be too tight - how does one adjust a cable on a car with ASR?
IAC question - i tried the depress the pedal, start and run for 5 seconds, shut down for 10 seconds and restart - still same high idle - 1500 RPM
am i doing it wrong?
do i hold the pedal in while starting and keep it "revved up"
or do i press the pedal, let go, then start? and run for 5 seconds? then shut down for 10 seconds and restart to check idle?
From the TECH TIPS section
tech tips say check pintle - WTF is a pintle?
i don't have my service manual yet (it's on the way) but i need to get this POS running ASAP!
getting ready to light car on fire, need help!
thanks
IAC question - i tried the depress the pedal, start and run for 5 seconds, shut down for 10 seconds and restart - still same high idle - 1500 RPM
am i doing it wrong?
do i hold the pedal in while starting and keep it "revved up"
or do i press the pedal, let go, then start? and run for 5 seconds? then shut down for 10 seconds and restart to check idle?
From the TECH TIPS section
This is from the 1994 GM Factory Serive Manual, Book 2: IDLE AIR CONTROL (IAC) VALVE Remove or Disconnect 1. Electrical connector from IAC valve. 2. IAC valve assembly attaching screws. 3. IAC valve assembly. NOTICE: On IAC valves that have been in service: Do not push or pull on the IAC valve pintle. The force required to move the pintle may damage the threads on the worm drive. Also, do not soak IAC valve in any liquid cleaner or solvent, as damage may result. Clean and Inspect Clean IAC valve and O-ring sealing surface, pintle, valve seat and air passage. The IAC valve may be cleaned using GM cleaner 1052626 or GM X-66A. Use a shop towel or parts brush to remove heavy deposits. Shiny spots on the pintle or seat are normal, and do not indicate misalignment or a bent pintle shaft. If air passage has heavy deposits, remove throttle body for complete cleaning. Inspect IAC valve and O-ring for cuts, cracks, or distortion. Replace if damaged. Important! If installing a new IAC valve, be sure to replace with an identical part. IAC valve pintle shape and diameter are designed for the specific application. Measure (If installing a New IAC Valve) Distance between tip of IAC valve pintle and mounting surface. If more than 28 mm, use finger pressure to slowly retract the pintle. The force required to retract the pintle of a new valve will not cause damage to the valve. Install or Connect 1. Lubricate IAC valve O-ring with clean engine oil. 2. IAC valve assembly. 3. IAC valve attaching screws. Tighten IAC valve attaching screws to 3 N-m (27 lb. in.). 4. Electrical connector to IAC valve 5. Reset IAC valve pintle position: A. Depress accelerator pedal slightly. B. Start engine and release accelerator pedal, run engine for 5 seconds. C. Turn ignition “OFF” for 10 seconds. D. Restart engine and check for proper idle operation.
i don't have my service manual yet (it's on the way) but i need to get this POS running ASAP!
getting ready to light car on fire, need help!
thanks
06-28-2005, 11:13 PM
#2
Racer
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To adjust the throttle cable, look for the one going from the asr box to the throttle body. There is a button on the cable, you can push in the button and slide the cable and see the throttle plate move back and forth. Move the cable until the plate is just touching the little screw in the throttle body.
06-29-2005, 11:44 AM
#4
Racer
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The button is in between the asr and throttlebody, closer to the asr. It's a funny looking cone shape on one end with a rectangle on the other. There are two other buttons that are similar also. I'm unable to post pictures.hope this helps any
06-29-2005, 01:42 PM
#5
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Thread Starter
well here's a mini update - this all started when i swapped out the throttle body to a 52mm from the 48mm stock, the idle was between 1000RPM and 2000RPM - so i figured the TB was "bad" so i removed it and put the 48MM "stocker" back on and it still idles at 1000RPM -
i have tried the IAC "reset" several times with no luck - anybody else got any ideas?
i have NOT adjusted anything else on the car, so i figured putting the OLD TB back on - it would go back to normal - well , no such luck!
now what?!?!?!?!?!
i have tried the IAC "reset" several times with no luck - anybody else got any ideas?
i have NOT adjusted anything else on the car, so i figured putting the OLD TB back on - it would go back to normal - well , no such luck!
now what?!?!?!?!?!
06-29-2005, 01:50 PM
#6
Safety Car
The pintal is on the IAC and is the part that extendes into the TB. There is an exact measurment of THAT extension. I don't have my books so I can't give you the measured length. Maybe someone will jump in with it. Did you mess with the IAC when you changed TB? It's possible the distance is off on the pintal in which case it will screw up your idle.
06-29-2005, 03:22 PM
#7
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Originally Posted by ittlfly
The pintal is on the IAC and is the part that extendes into the TB. There is an exact measurment of THAT extension. I don't have my books so I can't give you the measured length. Maybe someone will jump in with it. Did you mess with the IAC when you changed TB? It's possible the distance is off on the pintal in which case it will screw up your idle.
and NO i didn't mess with it at all (so it "should" be at the stting it was on before) - just pulled the entire "base" off the TB and transferred over to the other one - and then back again!
will a program like "freescan" or another engine monitoring program tell me about the IAC? like a setting of some sort?
i have a cable and FREESCAN and am trying to get it working - and would like to know if this is diagnosable - if i need a new one, then i need a new one - but would like to test first to make sure i'm not wasting my money on it.
06-29-2005, 03:55 PM
#8
Racer
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My '92 would idle about 1500 rpm's, no codes, no other problems. After going through everything that controls it, turned out to be a problem with the ECM. Got a reman unit from GM and no problem ever since, but I would try the cheap fixes mentioned above first. The timing of your changing the TB could have been a coincidence.
06-29-2005, 06:38 PM
#9
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Originally Posted by purplemajesty
My '92 would idle about 1500 rpm's, no codes, no other problems. After going through everything that controls it, turned out to be a problem with the ECM. Got a reman unit from GM and no problem ever since, but I would try the cheap fixes mentioned above first. The timing of your changing the TB could have been a coincidence.
i hope i can get my code checker working - i have a cable and software but can't seem to get my cable working as of yet - i'll make sure to post my results -
anybody know approximately how much a new IAC valve costs? it doesn't look hard to change, but does appear difficult to "configure" once it's installed
06-29-2005, 11:19 PM
#11
Melting Slicks
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Probably won't fix it but disconnect your battery for 10 minutes or so. Then it will be forced to relearn from ground zero. I believe the procedure you are talking about is only for the ASR, you shouldn't have to do that just to get the idle right.
Datamaster (though not free but you can try it for 20 runs) does tell you IAC counts - which gives you a good indication of what the IAC is trying to do.
Sounds like the IAC is bad to me.
If the throttle cable is too tight then you should be able to tell that - whether or not it is "resting" or not on the bracket tab it's attached to.
Datamaster (though not free but you can try it for 20 runs) does tell you IAC counts - which gives you a good indication of what the IAC is trying to do.
Sounds like the IAC is bad to me.
If the throttle cable is too tight then you should be able to tell that - whether or not it is "resting" or not on the bracket tab it's attached to.
06-29-2005, 11:35 PM
#12
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did the battery disconnect yesterday - had it disconnected for a couple hours - to be safe - started her up (again with the idle reset "trick" in tech tips) and it still idles at 1000-1100
i don't know WHAT procedure to use to get the ASR problem resolved - i hope it's a code i can reset with FREESCAN - i saw it has the ability to clear codes in there.
i don't know WHAT procedure to use to get the ASR problem resolved - i hope it's a code i can reset with FREESCAN - i saw it has the ability to clear codes in there.
06-30-2005, 12:29 PM
#14
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Originally Posted by ztrips
Does it idle that high if you take the throttle cable off the TB?
however, i have since put the OLD TB back on the car - and nothing was changed - so i'm gonna cave and put the 54 back on - and take off the cable and verify - that's a good idea!
any other ideas just in case?!?!?!?!?!?!?!
06-30-2005, 12:35 PM
#15
Pro
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Hi.
High idle may be vacuum leakage. Do check the vacuum hoses and the spray some startgas or propane over junction between the plenum (intake and the heads.
jan-erik
High idle may be vacuum leakage. Do check the vacuum hoses and the spray some startgas or propane over junction between the plenum (intake and the heads.
jan-erik
06-30-2005, 12:52 PM
#16
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Originally Posted by jan-erik
Hi.
High idle may be vacuum leakage. Do check the vacuum hoses and the spray some startgas or propane over junction between the plenum (intake and the heads.
jan-erik
High idle may be vacuum leakage. Do check the vacuum hoses and the spray some startgas or propane over junction between the plenum (intake and the heads.
jan-erik
maybe THIS is a dumb question - i did the TB coolant bypass while doing this change - but didn't plug the connectors for the hoses on the TB - could this be causing the problem?????
07-01-2005, 02:17 AM
#18
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THANK YOU THANK YOU THANK YOU EVERYONE!
turns out it was a couple different problems - first was my mistake, cuz, i'm an idiot!
when i swapped TBs there is the "base" of the TB that the heater hoses are connected to - when i disassembled it, i didn't see a gasket - therefore didn't realize i needed to put one on - but thought it odd because coolant was supposed to flow through that - but since i did the TB bypass, i didn't notice any "leaks" so i made a gasket for that as one wasn't readily available - had some gasket material laying around and voila! also replaced the TB to plenum gasket!
so with the throttle cable unhooked it idled NORMAL - with it hooked up, it idled high - so with the help of vetteracer92 - i was able to adjust the cable and it is purring like a kitten!
thanks everyone for your input!
turns out it was a couple different problems - first was my mistake, cuz, i'm an idiot!
when i swapped TBs there is the "base" of the TB that the heater hoses are connected to - when i disassembled it, i didn't see a gasket - therefore didn't realize i needed to put one on - but thought it odd because coolant was supposed to flow through that - but since i did the TB bypass, i didn't notice any "leaks" so i made a gasket for that as one wasn't readily available - had some gasket material laying around and voila! also replaced the TB to plenum gasket!
so with the throttle cable unhooked it idled NORMAL - with it hooked up, it idled high - so with the help of vetteracer92 - i was able to adjust the cable and it is purring like a kitten!
thanks everyone for your input!
07-01-2005, 07:39 PM
#19
Burning Brakes
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glad you figured it out.
by the way, the 28 mm measurement is from the surface where the valve mates with the TB (the "mounting surface" mentioned in the tech tip), to the tip of the pintle. There should be a paper gasket on the mounting surface.
by the way, the 28 mm measurement is from the surface where the valve mates with the TB (the "mounting surface" mentioned in the tech tip), to the tip of the pintle. There should be a paper gasket on the mounting surface.
07-01-2005, 11:15 PM
#20
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Originally Posted by tempest
glad you figured it out.
by the way, the 28 mm measurement is from the surface where the valve mates with the TB (the "mounting surface" mentioned in the tech tip), to the tip of the pintle. There should be a paper gasket on the mounting surface.
by the way, the 28 mm measurement is from the surface where the valve mates with the TB (the "mounting surface" mentioned in the tech tip), to the tip of the pintle. There should be a paper gasket on the mounting surface.
