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IACV/Idle advice 95 civic

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Old 07-17-2011
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IACV/Idle advice 95 civic

For those who have seen my incessant posting, I've fixed the 21 and 22 cel codes (had to run wires through the firewall, always fun...), so now I have no ecu codes, however I still have the bouncy idle (anywhere from 1300-2000, and sometimes settles at around 2000).
I pulled off the intake and covered the FITV hole (cold) suction; (warm) no suction- check.
Covered the IACV hole (cold and warm) lots of suction, and made the idle calm down. From reading the other threads this is no good... right?
Unplugged IACV (with car running)- calmed down the idle, but settled at around 1300.
Turned off car, unplugged iacv- idles at around 1500. I tried adjusting the idle screw on the TB (it was all the way in), didn't do much, eventually pulled it all the way out, only made idle bounce/jerky a little.
I once caught it with the idle settled (around 2K) and banged on the iacv with my screwdriver handle- that only made it bouncy again.
I checked the resistance across the posts on the iacv (just to see if the connection was open) i got about 33 ohms. I don't know if that's good or bad, but at least it's not an open circuit.
I just changed my radiator (hooray for junkyard day!), in case the little seeping leak in it was causing air bubbles in the system, and I bled the air from the system.
I've also sprayed around all the vacuum hoses to see if that made a difference, but it didn't.
I'm guessing that my iacv is stuck in the open position, creating a HUGE "vacuum leak", would you fine folks agree? Is there anything that I've missed and should do before I buy a new IACV and start throwing money at the problem?
Please advise.
Old 07-17-2011
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Re: IACV/Idle advice 95 civic

http://www.honda-tech.com/showthread.php?t=1575913
http://honda-tech.com/showthread.php?t=1564019
Old 07-17-2011
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Re: IACV/Idle advice 95 civic

Did both of those as a first step, sorry I should have included that as what I've done.
Old 07-20-2011
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Re: IACV/Idle advice 95 civic

So I swapped in a new IACV, reset the ecu, and now the idle surging has stopped, but the lowest I can get the idle is 1500. I'm thinking vacuum leak- any tricky places that I might miss when I spray with carb cleaner?
Old 08-15-2011
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Re: IACV/Idle advice 95 civic

So it turned out that the 'vacuum leak' turned out to the the throttle plate itself. I did just about everything in the book. When I took the tb off of the intake to change the tb gasket (which I was sure was the problem, it had a break in it when I took it off), after scrubbing the crap out of the intake throat, I noticed that the plate wasn't shutting all the way. I thought it was a factory thing, but after putting the tb back on with the new gasket with no change, I got mad. I put a screwdriver in the throttle pulley and pushed it towards the closed position, and it bent pretty easily (I wonder if the PO messed with it to get it to idle higher- you never know, people do weird things to their cars). And it fixed the idle. I pushed it as far as it would go and it brought the idle down to a steady, calm, non-fluctuating 500 rpm. I am still amazed. Whatever, it worked.
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