[me.]

im suddenly having a problem with my idle..at first it idled right at 600 rpms but lately its been dropping down to 3 or 400 then shooting up to 700. could it be the really hot weather?? it wasnt overheating at all. it was at normal operating temperatures. could this be a tell-tale sign of something bad going to happen...

 

[Gregg-O]

First thing that comes to mind would be a dirty IAC valve, or it's getting old and ready to give-up the ghost. IAC = Idle Air Control