[KAB 04 WJ]

Ok guys, I have been trying to track down a rather annoying engine noise.

Background - 2004 Grand Cherokee Laredo 4.0 I6, 45k

- I have been hearing a motor related noise coming from what I estimate is the front accessory drive. It only occurs at 2,000-2,300 rpms when the vehicle is in drive and under load.

- I can not replicate the sound when the truck is parked and I raise the rpms to to 2,000-2,300 rpm.

- To me it sounds like those older cars that have a screeching belt when it is really cold or wet outside. I can hear the noise everytime on the highway when I accelerate up through that rpm range.

- There is no noise when I let off the gas, so I assume that it is not drivetrain related. I am guessing it could be power steering or a water pump?

- There are no leaking fluids anywhere under the vehicle.

- The other odd thing in my mind is that I started hearing this noise after taking off my throttle body and cleaning it with throttle body cleaner.

Thoughts?

[gunthagunth]

My throttle body is pretty noisy right around where it shifts gears. If I'm on the highway and shooting along and the transmission is about to shift I get a nice whistle and if I'm going uphill and the transmission is struggling to shift it will whistle for a long time. Not sure what it is. I didnt know if it was my K&N or throttle body but I replaced the K&N with a tee shirt and the sound was still there.

[KAB 04 WJ]

I was reading the FSM and it says to use a new gasket when removing / installing the throttle body. I am going to pick one up on the way home and see if that gets rid of the noise.

[KAB 04 WJ]

Luckily a $3.00 throttle body gasket did the trick. The noise is gone! When all else fails, read the service manual.............before taking anything apart!