i agree with alex on this one. you dont have a balancer....though you do have a damper. these are known to fail after time.


now regarding the main and rod bearings.....a bad damper will cause these to fail but once a new damper is installed unless you actually spun a bearing (making a knocking noise) you wont have any issues. these engines are already known for having bearing issues so this is why i think the shop is jumping to that conclusion (if its not making any noise at this time)

there are many things that could be causing the random miss. loose or mispositioned timing wheel (the part that the sensor reads), ignition faults, fuel system faults, etc.


considering someone was just in there doing a belt it IS possible that the issue lies in that area.


regarding damaging the pulley to remove it....it is possible but considering you went 7k miles its not likely it was damaged during removal. 99% of the time the crank pulley will come off with just a little wiggling. being in PA it could have been rusted on. unless the tech that did the job was fresh out of school and that was his first timing belt job on a 6G he would have known how to properly remove it.


keep in mind in the 3000gt world many ppl install un-dapened pulleys with no ill effects even after 30-40k. (Personally i never will.)