2003 Malibu High Idle Again
nitrowildcat
08-27-2009, 06:10 AM
My 03 malibu has 70000 mls on it and a few weeks ago it started to idle high (around 2800-3400 rpm) after warm up. Sometimes it will stop diong it completely and other times it will fluctuate. I replaced IAC valve with an aftermarket one and it ran fine for about 5 days and started to do it again. Anyone else that has had this problem and knows a fix some help would be appriciated.:confused::banghead:
It has been a few weeks since I completed some work on my car and the high idle does not go away. After replaceing the IAC valve I removed the throttlebody and cleaned it till it looked new then when the when the problem came back the next day I took the car to a friend who own a shop and he hooked up his 20 grand Snap On computer and said the was a problem with the trottle position sensor. I replaced that (i think the code came from when i had it off and cleaning it ) the high idle came right back a couple of hours later. After reading in a forum someone else had done everything I had plus changed the intake air temp sensor so i did that, and it still didn't help.I have even ran some sea foam thru the car twice over the last couple of weeks. I did find some info on the intake manifold gasket leaking so With the car acting up I sprayed some carb cleaner around the edges of the intake to see if there was a change i idle speed but nothing happened. I was told by a friend that it could be leaking on the inside of the intake causing the high idle( all the vacume lines are ok ). Did notice a little bit of an oil residue in the coolant overflow tank, and im getting ready to flush out the coolant system today. 3 radiator shops told me to get rid of the dexcool in the car and go with the Prestone extended life stuff. Any advice on this would be appriciated.
P.S. It seems to start doing it now when the engine get up to operating temp and it has been running a little warmer as of late but not much.
It has been a few weeks since I completed some work on my car and the high idle does not go away. After replaceing the IAC valve I removed the throttlebody and cleaned it till it looked new then when the when the problem came back the next day I took the car to a friend who own a shop and he hooked up his 20 grand Snap On computer and said the was a problem with the trottle position sensor. I replaced that (i think the code came from when i had it off and cleaning it ) the high idle came right back a couple of hours later. After reading in a forum someone else had done everything I had plus changed the intake air temp sensor so i did that, and it still didn't help.I have even ran some sea foam thru the car twice over the last couple of weeks. I did find some info on the intake manifold gasket leaking so With the car acting up I sprayed some carb cleaner around the edges of the intake to see if there was a change i idle speed but nothing happened. I was told by a friend that it could be leaking on the inside of the intake causing the high idle( all the vacume lines are ok ). Did notice a little bit of an oil residue in the coolant overflow tank, and im getting ready to flush out the coolant system today. 3 radiator shops told me to get rid of the dexcool in the car and go with the Prestone extended life stuff. Any advice on this would be appriciated.
P.S. It seems to start doing it now when the engine get up to operating temp and it has been running a little warmer as of late but not much.
Johnny R
08-27-2009, 05:10 PM
You've got me stumped on the hi idle, but I would not for a minute believe that (i) Dexcool is the cause, and (ii) Dexcool should be tossed out in favour of Prestone. IMHO
nitrowildcat
08-28-2009, 06:08 PM
Could the high idle be caused by the intake manifold gasket leaking.
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