My engine was running a little rough. It wasn’t throwing any misfire codes, but when I replaced the spark plug wires, it ran so much better. A month later, now it is back to running rough.

I have the SRT6, so I have two plugs per cylinder

Will the car throw a code if one of the two plugs isn’t sparking? That’s why I figure it’s rough, but not throwing a misfire code. Is this right?

 

They all have two plugs per cylinder. Did you check to be sure a wire didn't come loose? Maybe one wasn't on all the way.

 

Oh, I thought only the SRT6 had the two plugs. Good to know!

I haven’t had a chance to look at the car, and there is a chance the wire came off. I was just wondering if the car would throw a code if 1 plug wasn’t firing

 

If a plug isn't firing you should get a couple codes. misfire knock, ignition coil, I would suspect your problem is a vacuum leak or the MAS Mas Air Flow sensor. That is just a guess, but they should all show a code. First thing is to double check your past work.

 

I was having a misfire code. I changed plugs and wires. Thought i fixed it but it came back. I found 5 of my coil packs had a crack in them.

 

This post reminded me of a commercial... " You say, you have a crack in your coil pack... I just want to say, heyyyy..." I think it was a commercial for windshields. Anyway, leakage during high engine demand (hard acceleration) would def cause misfires. Depending on where in the pack the crack is, it could easily be a lot worse. I would change all 6 since it seems that run of coils are bad (unless you're in a super-hot state and the car is running exceptionally hot). You might also see what you could do to cool down the engine compartment (if possible). Good luck!


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I changed all of them been running great. They were cracked on the back side.

 

GREAT to hear, am guessing that fixed all the misfire issues? A footnote cracked coils can be a he11acious thing to troubleshoot (as you know) because when one coil jumps, another could be close to 'jumping' at the same time. Your solution eliminates constantly opening up the engine cover for another 'jumping spark' issue in one step. I had two open coils on a 3.8L Babystar in my 89 Park Avenue. A little history, there were three coil packs firing the 6 cylinders and two of them output coils were 'open' internally. Under heavy loads there was a bucking bronco (that was) certified 'misfires'. Same motor in the 89 Le Sabre and those coils were 32 bucks each (the 'Park Avenue' coils were 138 bucks each and had a different part number, crooks I say!!!). Let us know if any more codes, OK? Enjoy!


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