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Hey all, this is my first post here, and I'm hoping someone has seen this issue before...
My 07 F150, 5.4L developed a misfire about a year ago on cylinder 8. I replaced all of the spark plugs and the problem went away for about 4 months. Then misfire came back, P0308, misfire cylinder 8. I replaced the spark plug and the coil pack. Problem went away.
This weekend, on my way to an elk hunt, driving uphill on the I17 in AZ at about 70 mph, misfire started again, this time worse than before. And this time P0308 and P0304, misfire cyl 8 and 4!
Took it to a shop, the coil pack was faulty on cyl 8, but cylinder 4 had a burnt up spark plug. I've never seen this before and was wondering if anyone had insight as to what would cause this to happen. Picture is below. This spark plug is 11 months old.
I was thinking possibly an injector stuck open, but the shop is saying that everything seems to be running fine now, and there are no more issues. Any help would be greatly appreciated!
Burnt up spark plug out of 5.4L Triton Cylinder 4.
Nowhere for them to go except down into the cylinder. I'm hoping the pieces were either burned up or small enough to get out through the exhaust. But if not, my problems may not be over.
Picking it up from the shop this morning, I had them do some other maintenance since I was there anyway. I was there yesterday, and they replaced the plug and fired it up. No knocking or any unusual noises. I'm planning on replacing all of the plugs with something other than motorcraft because those plugs seem to be a problem for a lot of people. I'm trying to decide if I should replace the injector as well.
Test the injectors and have them cleaned... you should stay with motorcraft plugs ...it's not the plugs fault...something causing it and it will not change with an aftermarket plug.
Test the injectors and have them cleaned... you should stay with motorcraft plugs ...it's not the plugs fault...something causing it and it will not change with an aftermarket plug.
You're right. The shop did a fuel system cleaning, and it's running pretty well now. I'll pull out my multi meter and test the injector. And on top of that, my driver side power window regulator just broke and the window is stuck down. Not a good week for my truck.
11-23-2015, 07:09 PM
Misfire - Burnt Spark Plug - Thoughts?
