kgshirk

Hello:

I am hoping someone can help me with some jeep problems I have been having. The dealership seems at a loss.

I have a '99 grand jeep cherokee w/ 94000 miles on it. It seems that every summer, when it gets hot out, if I take the jeep on longer drives, it starts making a rattling noise from under the car. Sounds like it is more toward the right side of the car, but definitely underneath. The sound is like something being caught in bike spokes, but more loud and exaggerated than that. Sometimes it gets quieter or goes away completely when I pass 40-50 mph. It gets worse and louder as I accelerate, but you can still hear it faintly when I am idle.

Car feels okay when it is running otherwise, so I don't feel like it is an engine problem. It only happens in the summer, so I feel it is heat related. However, this summer it seems to take less time for it to start happening (shorter trips). My dealership has heard it and checked the engine, fan belt, all the obvious things, and couldn't find anything. They said they unbent some "fan" thing, I can't remember what it was called, to see if that helped. It did help last summer...but this summer it is back.

Please tell me if you have any ideas? Thanks!

ol"blue

Does it make the noise with the AC turned off? It doesn't do it in the winter, but does in the summer, so I'm guessing it's AC related. Maybe the aux. cooling fan?

kgshirk

I have the AC on for the short trips and it doesn't make the noise. I have tried turning the AC off when I hear the noise and it doesn't stop the noise.

taterguy05

check your catolytic converter, the combs inside may be busted up...hapin the other weak in my 98 GC

just crank the car, get underneath and hit the converter

Sam David

Hello,

When you've said that it is heat related,, it would be a faulty electrical cooling fan which is mounted in the RHS. To check it start the jeep then turn on the AC, the fan should start and noise would come out if it's damaged,

Cheers...

kgshirk

Thanks everyone. I am going to check both those things. I will probably take it to the dealer with those suggestions if I can't find anything.