Forums Forums (
-   S-Series Tech (
-   -   High Idoling (

biglou17 09-21-2018 02:52 PM

High Idoling
I have a 2001 Saturn SC2. Im normally able to figure whats wrong with the car but not this time. My Saturn has issues idoling high. Sometimes I can start it up and its 100% fine and others the idol will race. When shifting into gear the rpms drop from 2k+ to around 1.5k. While driving due to the high rpms, im grinding down my breakpads trying to get it to stop. There are also times when im driving it, if i hit a stoplight and was sitting there for a while waiting for it to turn green the rpms would slowly roll down to 800 and then the issue would correct itself but if i wasnt there long enough for it to hit 800 then the issue would remain. The frist things I did was replaced the TPS and cleaned the throttle body with carb cleaner, I also cleaned out my EGR valve. Turned out that I was completely missing a vaccum hose on the back of the throttle body so i got one of those and put it on. After doing this the car had a hard time starting but after it did it seemed fine but the next day it was doing the same thing but now this time it would idol too low, around 500 rpm. i looked up the codes and ended up replacing the upstream O2 sensor. Where the exhaust manifold and engine connect, there was a ton of carbon build up there so I cleaned that all out as well. The car is still acting the same though. however this time, when the car starts normally, I am able to drive out of my neighborhood and as soon as I start getting to about 30mph, the idol jumps higher than normal. I have checked for vaccum leaks and so far i dont feel like I have any. I have checked this while the car was runnig at a normal rpm and also while it is high using carb cleaner. I have also completely covered the top of the throttle body during both and the engine cuts all air and dies. When I replaced the O2 sensor I did have codes but after replacing the O2 sensor, I reset the computer and now I have 0 codes, which im assuming is due to the computer still trying to figure what wrong. The codes I had before are P0507, P0122, P0133, and P0410. Any help would be appreciated.

Highmile 09-21-2018 03:35 PM

Re: High Idoling
First steps are easy..

check for vacuum leaks around the intake, very common issue.

clean the throttle body and the air idle control valve. It's best done by taking the throttle body off.

Good luck
'95 SL1 668k and counting

toggenburg 09-21-2018 03:36 PM

Re: High Idoling
When you went into the throttle body and the TPS, did you look at the IAC, it's right there?
I would replace the IAC and it should be a-ok.
Idle Air Control sensor= IAC

biglou17 09-21-2018 04:00 PM

Re: High Idoling
[QUOTE=toggenburg;2282473]When you went into the throttle body and the TPS, did you look at the IAC, it's right there?
I would replace the IAC and it should be a-ok.
Idle Air Control sensor= IAC[/QUOTE]

When I went into the throttle body to clean it all out, the rubber seal around the IAC connector(wiring) bent all ways and bunched up. When I tried to plug it back in I was getting alot of resistance due to the rubber band being worn and bunched up and I have to use alot of pressure to get the lock to fasten back on it. Do you think it may possibly just be a bad conncetion due to this and what is your opinion on just buying a new new rubber band as well with the new IAC to see if the band was the issue and if it was take the IAC back?

toggenburg 09-21-2018 04:49 PM

Re: High Idoling
That rubber band/gland is part of the harness itself, I would obtain one from a junk yard, and solder it in place of the damaged one you have.

biglou17 09-21-2018 07:55 PM

Re: High Idoling
I replaced the IAC and the car seems to be running fine at the moment. My issue has been fixed I believe. I will post back on here if the issue comes back. Thank you.

All times are GMT -4. The time now is 10:57 AM.

Powered by vBulletin® Version 3.8.9
Copyright ©2000 - 2019, vBulletin Solutions, Inc. The Saturn Enthusiasts Site.