Idle adjustment help
#1
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Year: 1990
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Engine: 4.0L Renix
Idle adjustment help
I just cleaned my filthy throttle body, and now my rigs idling at like 1200 at the beginning of start up, then after driving it's 1200 in drive and it's like I have cruise control on at 25 mph. In park it's idling at/around 2000 after a few minutes of driving.....I had a mechanic/friend of mind turn up my idle a few days ago before I changed my plugs, air, and fuel filters, and cleaned my throttle body because it was idling so low. Now that all that is good it's idling too high, but I can't for the life of my turn that idle screw down. There is a piece of metal in the way that prevents my screw driver to get in there to turn the screw. How do I bloody get in there? I should've watched my friend do it... also, where is the screw technically supposed to be stock? Is there a position for it from the factory that I should put it to or should I have my Jeep on while I'm adjusting it and wait until I get the RPMs to about 700?
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Make certain that you dont have any vacuum leaks like damaged TB Gasket, IAC damaged, etc. You can use carb cleaner, WD-40, spray around edge of the mating surfaces, idle will drop if you have a leak.
#3
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I don't have any, it's because the idle adjuster is sticking out holding the accelerator open.
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Is it the throttle lever in the way? If you push the throttle wide open, there shouldn't be anything in the way. Mine wasn't adjustable, it just had a tiny threaded stud the throttle rested on. I put a nut on the stud to idle mine up a little. Now, since i've addressed the problems I was having, I just removed the nut. As far as I know, your idle isn't supposed to be adjustable.. It should be controlled by the IAC. The little stud is only to keep the throttle slightly open. I'm sure it's preset at the factory. If you can't get to the stud, i'd suggest you (carefully) bend the lever where it contacts the stud. Good luck.
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Year: 1990
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That screw on the TB is to keep the butterfly from gouging the bore of the TB when closed. It is NOT to be used to set idle speed.
Loosen it up until the butterfly seats in the bore. Turn it in until you see the faintest movement of the butterfly. That's where it belongs. Get this remedied first.
Did you remove the TB, install a new gasket?
Loosen it up until the butterfly seats in the bore. Turn it in until you see the faintest movement of the butterfly. That's where it belongs. Get this remedied first.
Did you remove the TB, install a new gasket?
#7
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Is it the throttle lever in the way? If you push the throttle wide open, there shouldn't be anything in the way. Mine wasn't adjustable, it just had a tiny threaded stud the throttle rested on. I put a nut on the stud to idle mine up a little. Now, since i've addressed the problems I was having, I just removed the nut. As far as I know, your idle isn't supposed to be adjustable.. It should be controlled by the IAC. The little stud is only to keep the throttle slightly open. I'm sure it's preset at the factory. If you can't get to the stud, i'd suggest you (carefully) bend the lever where it contacts the stud. Good luck.
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#8
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Year: 1990
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That screw on the TB is to keep the butterfly from gouging the bore of the TB when closed. It is NOT to be used to set idle speed.
Loosen it up until the butterfly seats in the bore. Turn it in until you see the faintest movement of the butterfly. That's where it belongs. Get this remedied first.
Did you remove the TB, install a new gasket?
Loosen it up until the butterfly seats in the bore. Turn it in until you see the faintest movement of the butterfly. That's where it belongs. Get this remedied first.
Did you remove the TB, install a new gasket?
#9
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#10
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Okay what do you mean seats in the bore? Like is parallel with the wall? By the way I was just driving my Jeep again and it's so weird like it almost died and the idle dropped down to that little line just above the 0 one and I gave it gas so it didn't die and then I drive to go rent a movie and when I pull into my parking spot and put in in park the RPM's go up to 1500? I don't get it?
#11
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Not parallel. Turn the screw out til the butterfly no longer moves closed. Then, turn the screw in clockwise until you see the first bit of movement from the butterfly.
#12
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Okay. Well one of the questions I asked in the first post was how on earth do I fit a screwdriver in there to turn it? There is a metal piece that is bolted in which causes the screw driver to not get in line with the screw and it's up at an angle and it's near impossible to spin it. I'm assuming I probably just need a tiny screw driver.
#13
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It's a metric allen head screw.
#14
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Year: 1990
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idle air motor
throttle body gasket
intake leak ( cleaning can break stuff up)
check all your vac lines to you intake, and throttle body (all it takes is a bump, and its loose)
TPS, cruiser has the specs on that. if you hunt around you'll find them.
throttle body gasket
intake leak ( cleaning can break stuff up)
check all your vac lines to you intake, and throttle body (all it takes is a bump, and its loose)
TPS, cruiser has the specs on that. if you hunt around you'll find them.