the other day my SES light was on and the code was misfire on cyl. 6...i loomed my wires to separate them everywhere and then the SES light went away and car ran fine....for A DAY!!!...now i just got in from school and the car was running a temp of about 210..not bad....and now i have the SES light reading random/multiple misfires as i had b4 the cyl 6 misfire code...i seriously need some help as to what the problem could be...because i have a new coil/coil wire, new taylor ovcs, new ngk plugs, fire sleeving everywhere, looms to keep the wires from arching everywhere!!.....could it be my opti??? hopefully not but thats the only other thing i can think of with the ignition...

 

Is it possilbe the plug is loose or the porcelin is cracked? Possibly you hit it on something and closed the gap up when installing it? Defective wire or problem with the boot on the plug or on the Opti?

Could it be an injector? A faulty lifter? Compression issue?

 

And just curious.... why do you prefer to post engine related problems on "General...... Tech...." rather than LT1/LT4 Engine Tech?