2004 Pontiac Grand Am misfiring
Asked by Texas_1983 Feb 10, 2017 at 09:35 AM about the 2004 Pontiac Grand Am
Question type: Maintenance & Repair
My car began jerking at a light yesterday pretty
bad. Replaced all spark plugs and wires. Still
misfiring and difficulty accelerating. CEL is
flashing. Checked all spark plugs and wires and
they are good. Don't know what else to look at.
4 Answers
Possible causes; Faulty spark plug (s), Faulty ignition coil (s), Clogged or faulty fuel injector (s), Intake air leak, Fuel injectors harness is open or shorted, Fuel Injectors circuit poor electrical connection, Ignition coils harness is open or shorted, Ignition coils circuit poor electrical connection, Insufficient cylinders compression, Incorrect fuel pressure.
May want to run some fuel injection cleaner threw the gas tank also, here is a note from GM fuel injection cleaners...GM UPPER ENGINE AND FUEL INJECTOR CLEANER is the only injector cleaning agent approved for use with General Motors fuel system components. Other injector cleaners may cause damage to plastics, plated metals or bearings. General Motors has completed extensive laboratory testing of GM Upper Engine and Fuel Injector Cleaner, and can assure its compatibility with General Motors fuel system components.
