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Lagging/Surging RPM's-Help!
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Old 24 Jul 2007, 02:43 AM   #1 (permalink)
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Thumbs down Lagging/Surging RPM's-Help!

So I recently bought a 1995 1.8L Impreza with around 154K; its been a nightmare. First the starter went out and now I'm having another annoying issue:

First and foremost, when I start the car, the RPM's surge to almost 2500. SOMETIMES, the RPM's will then return to the normal idle position of 750 to 1000, BUT most of the time it remains high (around 1500 to 2500).

Second, while driving, the RPM's will stay high. Its kinda like having cruise control. I'll be coasting, without my foot on the gas, and the car will stay at 2000+ rpm's in any gear. It almost feels like the car gives itself gas. Weird.

Third, sometimes when i come to a stop sign and put the clutch in and shift to nuetral, the RPM's will surge to 2000 then climb to 2500 and even to 3500 somtimes; no foot on the gas, transmission in nuetral.

Anyway, if anyone has any ideas whatsoever, please, please, let me know. Thanks.
-Nate from Seattle
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Old 24 Jul 2007, 11:35 AM   #2 (permalink)
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idle control valve maybe? or perhaps maf?
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Old 24 Jul 2007, 12:09 PM   #3 (permalink)
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yep, sounds like idle control valve or maf... why not reset ecu and see if it throws up any blink codes... see top of this forum for advice on how to do so...
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Old 25 Jul 2007, 08:15 PM   #4 (permalink)
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Do work son...

So I did work today and cleaned the MAF, sprayed the sheeit out of the throttle body and tried to get some up in the IACV (I didn't want to take it off since the bolts are soft and I didn't have a new gasket handy). Then I put some injector cleaner in and I even reset the ECU.
The ECU threw up what I think is the OK code. A.K.A. the steady one second blinks. (Although I thought it was supposed to be steady half second blinks, is there a difference?)
After the test run, the car still idled high but the RPM's did not seem to surge. So when I got back to the house I adjusted the idle screw until it idled at a steady 1000-1100 rpm.
So after I head to work and drive it for a little I'll throw an update on here about how she did. Cross your fingers boys and girls...and thanks for the helpful ideas; we'll see how it turns out.
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Old 25 Jul 2007, 08:32 PM   #5 (permalink)
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cool, glad its sorted
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