Hello all, I have a 2007 Cobalt SS 2.4L (manual) with about 23,000 miles on it. About three days ago i started noticing a slight rattle when i starting her up, and also when shifting between first and third gears from time to time. It is not continuous while driving, and I get no check ingine lights for feel no difference while driving. The noise kind of resembles the sound of pebbles in the muffler......This rattle is extremely aggrivating! Can anyone please help me or give me some idea as to what it may be?

 

chances are its your ECM cover, or ECM itself.

Take the cover off, and have a friend hold the ecm itself and start the car and see if it goes away.


its something vibrating, because going off of your post, you hear it sometimes, but not always.

so chances are its rattling from the vibrations of your engine (lower rpms = higher vibrations).



best bet to fix if it is your ecm itself, is to get a piece of foam and shove it behind the ecm.


i also notice my glove box is rattling more so now than before, so now i have to figure out a way to fix that.



Good luck to you.

 

I had a rattling problem too just like this.

Rear plate was loose a bit. 20 second fix.

 

Rear plate of the ECM? I have a very annoying rattle that I haven't been able to find so far.....during shifting at around 2500-2700 rpm........it's brutal. I would rejoice if I could find the damn thing.

 

so was it the rear ECM plate?

 

tick tick ... rattle rattle

 

that helps

 

Not on mine......rattle is still there.