2006 Chevy Colorado 6 cyl Two Wheel Drive Automatic 75000 miles
My truck started to have a rattle/vibration at idle. This happens for a one or two second interval at idle, stops for about 30 seconds and repeats. This only happens at idle either in or out of gear. Once I hit the gas the rattle/vibration stops. I replaced the belt, no fix. Then the tensioner, no fix. I opened the hood and listened and it sounds like something is loose. Looked around and everything is fine. I kinda think it is the alternator, since I can initiate the rattle/vibration by lowering the power windows. The RPM's at idle are around 650, which has always been normal. Then the rattle/vibration starts I can see a slight change in RPM's, usually less than 100. Thanks for any suggestions.
Try removing ht edrive belt to see if it stil makes the noise, only run it for a short period of time though.I fnoise is gone, then you know it is a belt driven acessory that is doing it. With belt off, engine off, try spinning all accessories to see if any make noise or feel rough like the bearings are bad
November, 12, 2008 AT 8:54 PM
I had a very similar rattle on my 05 colorado, drove me absolutely nuts. Sounded like it was coming from the engine compartment. At first I thought it was the guts in the catalytic converter, then I took it to the dealership they had to replace an exhaust mount near the transmission and " reposition" exhaust. This fixed my problem.