Weird 5k rpm stumble and knock with AEM F/IC
Posted: Sun Dec 11, 2011 8:26 am
oh electrical wizards of legacy central I have a problem that could really use your genius.
its a 5k stutter and knock on my ej20g with ej22t ecu and ignition with a aem f/ic here's what I know.
-doesnt happen when car is cold
-got worse when I went to colder plugs
-my tuner confident not a tuning issue
-switched coil packs out with no change
-fairly well grounded 2ga ground wires from block and chassis
-does it at same rpm whether full throttle half throttle or quarter throttle.
-developed a few months ago sometime after the f/ic was installed
-reset ecu with no change
-when I pulled plugs they all looked like they were supposed to
-occasional miss at idle
-when I log it air fuels seem to spike like the ecu is pulling fuel
-under 4000 rpm car drives and pulls great
-rewired the power and grounds to f/ic
-changed alternator
i feel like i have covered everything i can think of, and don't know what to do next
its a 5k stutter and knock on my ej20g with ej22t ecu and ignition with a aem f/ic here's what I know.
-doesnt happen when car is cold
-got worse when I went to colder plugs
-my tuner confident not a tuning issue
-switched coil packs out with no change
-fairly well grounded 2ga ground wires from block and chassis
-does it at same rpm whether full throttle half throttle or quarter throttle.
-developed a few months ago sometime after the f/ic was installed
-reset ecu with no change
-when I pulled plugs they all looked like they were supposed to
-occasional miss at idle
-when I log it air fuels seem to spike like the ecu is pulling fuel
-under 4000 rpm car drives and pulls great
-rewired the power and grounds to f/ic
-changed alternator
i feel like i have covered everything i can think of, and don't know what to do next