Sticking Idle

[DJAMiller]

Hey guys, I have an odd problem that only happens occasionally, once and a while if I'm cruising or whatever at say 2,000 rpm and I push in the clutch the engine will stay at 2,000 rpm until the transmission forces the idle down, at which point it will stick to whatever the rpm range is then. If I restart the car it immediately fixes the problem. Anyone have any idea what could be causing this? IAC perhaps? The problem is that it does it so rarely I cant really get it to do it when I want in order to properly diagnose it.

 

[my04mach]

This is a pretty common issue with the Mach's. At least, that's what I've noticed over the past five years I've had mine. Mine did this occasionally when I had my JLT next gen cold air kit on the car. I haven't noticed it happen since putting my stock cold air setup back on (including my MAF screen). Some Mach's with certain manufacturers of cold air setups seem to experience this problem as well, but it didn't happen that often at all with the JLT I had. Does yours have an aftermarket cold air setup?

If it's more than just hanging idle, like it can't find a happy idle spot, etc I'd say it could be the IAC. I've replaced mine once due to some issues I was have that turned out to be excess oil from a new S&B filter replacement I bought for the JLT I had. I bought a Motorcraft IAC from RockAuto and it was bad, believe it or not. I'd buy one local so it's easier to return it if it's bad. I put put the stock IAC back on when I went back to my stock cold air setup and it's worked fine. Sorry the response was so long lol.


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