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Discussion Starter · #1 ·
i have a 90 lx that i am doing a 4 to 8 sway and i just got it running but it idles at 1100 to 1300 rpm, so i cleaned the idle air valve, but then it idles at 2000, i read that silicone is bad on anything with vacuum so i got a new gasket and a new valve but reused the solenoid and it still idles high, i heard that you can adjust or calibrate the valve but i dont, any one run into this or have any suggestions?
 

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Are all of your vacuum ports taped or plugged? Under the upper intake?
Verify the correct timing, and then start performing electrical checks of sensors. I assume you've adjusted the throttle plate stop screw.
 

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If it's idleing at 2 grand just after the idle air control valve was cleaned , then I bet you put the valve on backwards . it will bolt up two ways . just make sure the electrical connection is on the bottom . Other than that , most likely a vaccuum line is off . And if you adjusted the screw on the throttle body to try to get the idle down , then you should re-adjust the throttle position sensor .
 

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Discussion Starter · #5 ·
its installed like the pic, if i unplug the idle goes to 750 and never goes up or down except cold for like 30 seconds i have to help it idle, all the vacuum lines are pluged and i am sure there are no vacuum leaks, the timing is set at 10 degrees with the spout out, how do you adjust the iac motor? thanks
 

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Now I have a high idle problem. Started about two weeks ago after a night of hard driving and lots of rubber. Car consistently idles at 1500. Used to be 800-900 solid. I have thoroughly cleaned the mass air meter and the IAC. In fact, I have two different IAC valves and the car idles the same regardless of which one is installed. Thought I had identified a vacuum leak under the upper intake manifold but it is still doing it. I have one of those idle adjust plates between the IAC and the throttle body, but doesn't seem to make a difference in the car's idle speed. I also checked the timing and it is right on 10 deg. The only thing else I can think of is a vacuum leak between the lower intake manifold and the heads / block. Anything else?
 

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you know what i had the same problem and nothing would fix it i checked everything and cleaned everything. if all that doesnt work go to 50resto.com
and look for a IAC adj. plate. that fixed it for me. they are the only ppl that carry it that i found. and you just put the plate in between the IAC and the TB and turn the high idle down. works like a charm!
 

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I went to the 50resto.com site and couldn't find the part you were talking baout? What does the plate do?
 

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i would check and see what the throttle position sensor is reading, if it is low then either it needs a new one or needs to be reset.
 
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