Did you figure out what was causing the noise?
I have exactly the same problem. Recently I have had the water pump replaced. The noise appeared just after this repair. The engine works fine at cold, the noise appears when temperature reaches certain level and it’s audible only at low rpms. It goes away when you slightly increase the rpms.
The mechanic who replaced the water pump says that the engine might have been overheated, which is not true I believe. I had a water pump failure but it was an exterior leak and I noticed it very quickly (after 1 mile trip to a grocery store…). I didn’t lose too much coolant. Then the car was towed away.
I have a 2002 intrepid 2.7 with 155k miles on it. Here is the video :
Last edited by Le Vinh; 09-17-2012 at 10:23 AM.