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Unread 08-20-2012, 12:36 PM   #1
seanom
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Another High Idle Question (have read a few..)

So I get high idle in park and neutral only after driving for a little while. I also have been getting a hard start.

High idle happened for about a week, then hard start, so I cleaned the Throttle Body and the AIC with cleaner and also sea foamed the engine. I threw some fuel injector cleaner in a full tank too.. just for fun.

Problem went away for about 2 weeks and now is back, maybe even a little worse.

Mainly wondering why being warm would create the High Idle; it only hard starts when cold (kindof obvious)

2 more things: the exhaust system fell off while on the highway (during problems, before cleaning), so cat muffle etc..

and I haven't reset the trouble code yet- was going to do that today, but forgot my laptop at a buddies.

I think most likely its the TPS or AIC does TPS make for a hard start? It seems strange that the high idle doesn't come on until after Iv'e been driving instead of right away.

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Unread 08-20-2012, 06:18 PM   #2
ZeeJay1997
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May be caused by a leaking intake manifold gasket. Throws the MAP sensor off.
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Unread 08-21-2012, 07:41 AM   #3
gothchick
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My vote is on TPS. Dealership can run a scan tool on it to check voltage range. They generally don't charge for little stuff like that.
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Unread 08-21-2012, 08:47 AM   #4
Canyon411
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You mentioned your exhaust is gone, what about the 02 sensors? Are they missing as well?
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Unread 08-21-2012, 11:37 AM   #5
seanom
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Quote:
Originally Posted by Canyon411 View Post
You mentioned your exhaust is gone, what about the 02 sensors? Are they missing as well?
I put it back on; but I am wondering alittle if that 02 sensor could have been damaged causing some of these results.

I wish I didn't have to.. damn that thing is loud without a muffler or cat

It's too loud when the sound is coming from under your feet tho
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Unread 08-21-2012, 11:39 AM   #6
seanom
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Quote:
Originally Posted by ZeeJay1997 View Post
May be caused by a leaking intake manifold gasket. Throws the MAP sensor off.
I checked for vacuum leaks with started fluid, couldn't find any - I was mainly checking the hoses tho.
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Unread 08-21-2012, 11:40 AM   #7
seanom
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Quote:
Originally Posted by gothchick View Post
My vote is on TPS. Dealership can run a scan tool on it to check voltage range. They generally don't charge for little stuff like that.
Cool - Ill give em a call or see if I have the equipment kicking around here
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Unread 08-21-2012, 05:59 PM   #8
seanom
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I just ran codes and got P1294 (comes on and off it seems) as well as P0138 (02 sensor Cir. High. Volt.)

I'm going to try clearing them as I haven't since the exhaust fell off and I cleaned everything
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Unread 09-02-2012, 01:03 PM   #9
seanom
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so I just went ahead and bought a new TPS, everything is still the same... Hard start is worse. I cleared the codes after the install. I couldn't clean the MAP becasause the damn aircon was in the way. Gonna rip that out soon.

Any ideas? would O2 sensor after the cat make for a hard start?
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Unread 09-03-2012, 09:52 AM   #10
seanom
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bump...
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Unread 09-03-2012, 09:13 PM   #11
gothchick
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Hard start may be as simple as a good ol' fashioned tuneup...
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hard start , high idle , iac , tps , zj

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