2002 Mitsubishi Eclipse Starts, runs fine, but won't idle.
Check for codes. I think you might have an issue with either - - #1) The ISC (Idle Speed Controller) or IAC (Idle Air Controller) might be broken due to age and no longer able to control the idle correctly. OR #2) the EGR valve opening is filled with crude at the end of the "tip" (facing into the exhaust system, not on the outside) so that the EGR valve can not work correctly and that would cause the idle to be off.
id addition to what Fordtudor has said id think that the fuel pressure regulator might be something to look at as well, also if there is a check engine light get it scanned and see what you find out
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