idle problem

I have a 2000 ford ranger 4 cylinder 5 speed. While i am driving it and come to a stop the idle revs up and stays there for a while and then go down. any ideas on what could cause this?

I suspect a vacuum leak somewhere, (possibly related to a defective power brake booster) or a defective idle air controller.

There's an Idle Air Control valve that opens and closes when you're idling to make the engine run properly without stalling. It's found on the intake manifold. I suggest looking at that first, and make sure it doesn't take forever to close. A vacuum leak would cause high idle in general, or so i would assume.

Thanks for the information i will take a look at both items.

i had a ranger with that problem.
vacuum line came undone.
good luck!

thanks for the info i will look for it.