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I had been having an intermittent symptom of what I believed to be a misfire but it would never cause a CEL to come up. Luckily, on Friday while at the shop having the oil changed, it finally threw a code when they were re-setting the service meter. Checking the code revealed it was a misfire on cylinder 7. I previously purchased a new set of plugs with the intention of changing them so I went home, turned the A/C down in the garage and tackled that task that evening.
Taking the coil packs off was, by far, the hardest part of changing the spark plugs. But now that I've done it I don't think it'll be as difficult next time. Got the plugs out and overall all they seemed fine with the exception of the cylinder 7 plug.
The insulator for the center electrode was loose and covered the electrode, thus the misfire. Has anyone else experienced this before? Any ideas as to what can cause this? Possibly just a manufacturing defect in the plug?
The plugs on cylinders 4 and 8 looked a bit darker than the rest, possibly running a little rich? Other than that they all looked good to me. I welcome any other thoughts.
I had a misfire recently in cylinder one and had the coils for that cylinder and all plugs replaced. Misfires seem to be quite common for our cars and usually its the coils that causes the issue.
Haven't seen that happen to a spark plug before, could be a defect or could of happened due to the misfire. Since you have changed all plugs now, if you do have another misfire then it's most likely your coils for that cylinder.
I had a misfire recently in cylinder one and had the coils for that cylinder and all plugs replaced. Misfires seem to be quite common for our cars and usually its the coils that causes the issue.
Haven't seen that happen to a spark plug before, could be a defect or could of happened due to the misfire. Since you have changed all plugs now, if you do have another misfire then it's most likely your coils for that cylinder.
Originally Posted by Trevor Hadley
L;ucky to have seen that it is now rial and error time ...hope it all good and nothing else .
Misfire is gone and the car is running great. But yeah, figured I would start with the plugs then order a new coil pack if needed. Did not end up needing to get to step 2.
Originally Posted by amg8
I would say consider yourself extremely lucky. Imagine if the insulator broke in pieces and it fell into your cylinder.
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