i bought a grand cherokee 97 5.2 and the motor has a problem ,,you rev it and when the rpms are going down it dies and / or idles roughly also the motor overheats <<< it leaks all the water but dont konw if it is the radiator or a simple hose. anyone have an idea? thanks.

How many miles on it?

More than likely has a blown plenum gasket (very common) that can cause a funky idle, and make it knock like a sum bitch.

Check the IAC solenoid in the t/b as well.

How much coolant is it losing? Is it dumping on the driveway or just mysteriously disappearing?

If it's a high mileage (150k+) prob needs a timing chain, good tune up, and a few other little things.

thanks i took the radiator off and was very bad i am having it welded tomorrow then i will try to fix the motosr prob. it has 127,000 miles.

Its more than likely the IAC on the throttle body. I had the same problem a few year ago on my 97' 5.9L and I replaced that and problem was gone!! Hope this helps!!!

Be sure to check for exhaust gas in the radiator... if the plenum gasket blows, most likely the water is in the oil but if the head gaskets are leaking, then if it is not yet going into the oil it is going out the tailpipe..... will be in the oil soon

thanks turned out to be the spark plugs and i cleaned the thtotle body with carb cleaner. the transmision would not let the truck run freely at start but it was a sensor ,,its running great now. i even beat a durango hemi sweet.

good to hear it wasnt anything major!!!