Engine or Exhaust rattling?
2003 gt cats back exhaust, CAI, Plenum, TB, SCT tune done professionally.
Sounded like a pinging noise at first. It will usually happens in 5th and I have the five speed. If you have the car in low RPM lets say 2,000 in 5th it will make a very distinct rattling / pinging noise under acceleration.
It doesn't happen at idle or anything other then just sometimes in 4th which is even more strange. Also it doesn't do it all the time, but it does occur quite often. When it happens I usually throw it into a lower gear and it goes away. I believe my tranny mounts are in good condition so probably not that.
Now the guy who tuned my car said he is absolutely sure its not pinging but the noise is very very similar.
I was thinking it might be a clogged cat I'm not sure any ideas in the right direction will help thanks.