is there anyone out there that can help me,
i dont know whats wrong with my Gst,
i was getting on the interstate yesterday and at 3500rpm it was sputtering a little , then it back fired twice.
when i got off i was getting a very rough idle and it took me a little longer than usual to get up to the speed limit, it just seems like it wont let me go any faster than 75-80mph
and it sputters at 3500 to 4500 rpms and sometimes i cannot go over 4000 rpms, someone please help with this problem, i have no idea, hope it is cheap to fix.

I am sorry if i broke any forum rules by not spelling right.