03gt04mach1

I know the IAC valve has been beaten to death on the forum, but I have an issue with RPM surge when coasting down steep hills after acceleration. Between 1-2 hundred rpm back and forth. And not all the time. And when I put it in park, the rpm goes up 4-5 hundred and drops down and idles around 750 nice and even. Is this just the beginning of an IAC problem? I give my thanks for your input.

Frostbitten

could be a vaccum leak

03gt04mach1

I thought that too. But, all hoses are secure. I noticed at work, there is a lot of dirt blowing around from construction lately. They are adding on to the building I work at. It reminds me of sand storms in the desert. Since my Air Filter is in the fenderwell, some fine particles may have gotten through. So, I'm going to clean the MAF sensor and I'm still going to get a Motorcraft IAC valve, just in case. And clean the filter. Thanks