New plugs-EGR working- misfires under light load but runs smooth and strong upon accelleration. Where to look? Short post due to forum problem

 

Hopefully, I can add more text here in a second post. The ECU threw a P0304(#4 misfire, and the CEL blinks during the misfiring-according to the owner) It really vibrates at a feathered throttle, but runs strong and smooth upon acceleration. It is getting new wires, dist cap and button today, but I doubt that is the fix. Could it be the tranny(torque lockup)Will report back.

 

Tranny & TC might FEEL like a misfire, but they shouldnt set off P0304.

 

check your fuel injectors. i had the same issues with my car before and i had my fuel injectors cleaned and yeah i also cleaned up my plenum chamber on my intake. and that really help out a lot.
although my CEL was for the #1 cylinder misfire,that code did not go away but my acceleration from a dead stop improved dramatically and even on just normal city driving it really changed after getting those 2 things done. my CEL issues went away after i replaced my ECM.

 

I guess that the injectors is the next step. After new plugs, leads, dist cap and buttonthe missing under light load is still there. But that should eliminate the misfire code eventually.
Best method of cleaning the injectors????????? Thanks

 

i sent mine out to a injector shop close to my area.got it back within 2 weeks. fairly cheap. they basically overhauled it and place new o-rings and all parts that needed replacing. hope that help.

 

Make sure your injector oring (injector/manifold)is tight and not leaking air into manifold. This might cause a lean miss. If that doesn't show anything, suggest swapping injectors to see if problem follows injector. If yes, I would get a used replacement.

good luck