Hey guys,

I was on the highway today and drove for ~60 miles or so. Once i got off the highway and was at a stoplight i noticed my idle was around 1500rpm, not the usual 550-800 rpm range. After driving through the next couple of stoplights, my idle shifted back down to the normal 600 rpm range.

What would cause this? I have read a few threads already and previous members mentioned it could be anything from the throttle body, IACV, vacuum hoses, or even the ECTS. Has anybody experienced this issue before and resolved it? I have always had this issue high idle issue since I bought the car 3 years ago and have yet to find a solution.

Any input would help.

 

The cause would be sticky deposits inside the iacv.

The fact that the idle eventsully returns to norm as l more or less confirms this.

I took mine apart. Then I cleaned all parts and passages with carburetor cleaner. I reassembled it.
Then put it back on the car with a new gasket.

Note. There are some adjusment screws on the side of the iacv. Count how many turns of the screwdriver it took to remove them. Write that number down. Clean the passages behind where the screws live. Be sure to turn each screw the same number of turns it took to remove them.

Those screws control idle speed.

Might as well clean out the throttle body while you are in there anyway.

You will need a can of CRC Throttle Body Cleaner from the parts store. Do NOT use carb cleaner.

Also an old toothbrush

Also the gasket between the tb and the uim.

Remove tb.

spray it down inside with the tb cleaner. Srcub with toothbrush . Especially the edges of the throttle plate and where that meets the throttle body.
Clean out any passages.

Your car should run smoother than before , and have a stable idle.

You will be able to use the chemicals in future years.
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A small air leak In a hose perhaps...

 

That was my first thought.

Would the idle speed go down by its self though?