ghoste

Anybody come across this issue? When I replaced my intake manifold, I threw in some ngk iridium's, and it misfired under load. So I took out all of the plugs in the driver side bank, and replaced them with the stock plugs. Misfiring went away. Now, this weekend, I decided to take those new plugs I took out, and test each one of them in 1 cylinder. I tested all 4, under load, no misfiring. Come today, its misfiring again.

I dont understand, could it be an A/F ratio problem, mysterious plug, or compression problem?

tripsevn7

r u running stock coil packs? i ran densos' in my 98 with msd ignition and loved em. never had a problem. didnt have a stock ignition either though.

ghoste

My narrowband a/f gauge is showing lean to slight stoich

ghoste

yes, stock coils.

tripsevn7

hmm showing lean? did you check it with the stock plugs as well? what is your a/f then.

ghoste

same.

ghoste

But when it WASNT misfiring, I had 4 iridiums in the passenger side bank, and 4 of my stock plugs in the driver side. It only misfires when I put all 8 new plugs in.

ghoste

Help! [&:]

Phirantes

Ghoste i'm guessing you replaced your intake cause it cracked and leaked water every where. If thats the case its probably one of your Coil-on-plugs. I had three COP that would short out and the run fine for a while then short out again.... It ran like that for 3 months before it even threw a CEL because it was never a regular misfire. Take it to your local Ford dealership and pay the $76 for them to diagnose which ones are shorting out (unless you can figure out which ones are for sure problematic). Then go to your local junkyard and and buy some coils ( believe me they have a box FULL of them), if you work em right you could probably get them for around $10 a piece instead of the normal $100. Then replace yourself. Hope this helps

ghoste

I highly doubt its a COP, due to the fact when I put my old 4 plugs back in, misfire is gone.