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Very Poor Idle 2003 Galant 2.4L

Inman Lanier
08-01-2009, 04:38 PM
My car has 131K miles and has been very reliable. My boys commented that the idle was quite rough and the car would stall. Usually this is the idle air motor ($300 just for the rinky-dink part!!!). I noticed that it happened when the compressor kicked on - if you turned the A/C off, although low in speed and a little rough, it wouldn't idle super low. It was the compressor that would pull it down and kill it. I also noticed that when you started in the morning, the idle would go up some, then settle slower and get rough - the fact that it went up told me that the idle air motor at least worked some.
After reading posts and getting sticker shock on the part, I decided to remove the throttle body, then idle air motor, clean them up and reinstall to see what would happen. If worse came to worst, I'd do the manual bypass valve adjustment to try and get the speed high enough not to stall.
Both the throttle body and idle air motor had deposits. I use a K&N filter so these may have been deposits from the oil on the filter. I cleaned them up (had to use a screw driver to scrape the throttle butterfly clean). I then opened up the manual bypass air screw a couple of turns. (it was stuck, took some penetrant and patience).
I put everything back on, started it up, made some adjustment of the manual bypass screw and now it idles more or less like it used to.
Didn't need a new motor. I wonder how many folks pay for a new idle air motor when all it needs is cleaning.

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