GMC Troubleshooting Questions? Ask a Mechanic for Answers
i am sorry your having this problem
the mechanic confirmed it was JUST % 5 cylinder doing this ?
if this is only a specific cylinder then the fuel pump should not be the issue
these issues come down to a bad cap and rotor bad # ***** plug ot plug wire OR sticking valves in the valve guides for # ***** cylinder which is somewhat of a common issue with these 5.7 R engines
how are you making out ?