High Speed Miss [Archive] - GrandAmGT.com Forum


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10-07-2008, 10:46 AM
Problem is identified by a SES code of #2 cylinder missing, yes I know where it is. I replaced the spark plugs, plug wires, fuel filter, and air filter. Did not solve problem , then replaced the #2/6 coil pack, swapped wire, swapped plugs, did a compression check (150 psi). What next should I check before I swap the ignition module under the coil paks or take it to the dealer? The ignition module is $200++ from GM.


10-07-2008, 12:52 PM
could be as simple as a dirty injector. i'd run some seafoam through, and go from there. its best to start simple.

10-07-2008, 07:38 PM
Seconded. Dirty injector can cause that. You've eliminated all the obvious ignition issues and you have good compression. Last thing is fuel.

gagt Mechanic
10-09-2008, 09:23 PM
get a test light and hook it up to your neg batt term, run it along wires to make sure you do not have any arking wires. new does not mean good all the time.

10-09-2008, 11:08 PM
If the problem exsisted before and after the new wires were installed, that rules them out. You'd also have to have horrible luck to end up with a single cylinder misfire with a brand new wire.

10-10-2008, 07:13 AM
I ran a can of Seafoam through with no effect. Another thing we did was swap the #2 fuel injector with an adjacent cylinder, with no change in perfromance or code 0302.