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CCSB with the 6.2 gasser. 57000 miles. Getting a P0302 misfire code on the second cylinder. In looking things over, I noticed the plug wire has experienced a fair bit of rubbing. See photo. Have others seen this?
Curious if this seems like enough wear to be causing the misfire. The truck actually idles and runs great. I haven’t noticed any loss of power or change in performance. Just the check engine light/code.
It's been my experience with previous gasoline vehicles, that reported misfires are due to a fuel injector problem. If left long enough and not corrected, the excess fuel will foul your catalytic converter (that will have to be replaced at that point).
Not the greatest photo. But yes. The cylinder 2 wire. The way it’s routed it is rubbing on the adjacent plastic vent tube. Doesn’t seem practical that it would be shorting out to a piece of plastic.
Kind of hoping it’s an injector, as that would be covered under the warranty. In doing some research, it looks like the ignition coils are only covered up to 50,000 miles under the emissions warranty, but easy to replace.
That little bit of rub probably isn't going to cause a problem. Look at it in the dark while someone is power braking the engine. Just stand off to the side with the hood open, have them put it in gear with their foot on the brake (use reverse for extra caution) and press the accelerator pedal to put a load on the engine. Peak voltage is low at idle, but if you can increase the pressure in the cylinder it will take more power to jump the gap on the plug. That is when it might find an easier path to ground by jumping out of the wire. If you don't see any sparks you can also listen for the clicking sound it makes.
The 6.2L is a coil-on-plug engine and they have corrosion issues with the coil packs like my old 5.4L F-150 did. The ports on the coil packs will corrode and create issues like the ones you are having. Took me forever to figure it out, truck would skip only at certain RPM and under load, like climbing a hill. Turns out moisture had collected down in the hole where the spark plug and it's boot go and that lead to the corrosion issue. You can't "fix" it, you just need to clean the corrosion out of the coil pack connections as part of your regular maintenance. Like my 5.4L that's the only issue you will likely ever have with this engine.
But the coil-on-plug thing was the tipping point in ordering the 7.3 for me.
The 6.2L is a coil-on-plug engine and they have corrosion issues with the coil packs like my old 5.4L F-150 did. The ports on the coil packs will corrode and create issues like the ones you are having. Took me forever to figure it out, truck would skip only at certain RPM and under load, like climbing a hill. Turns out moisture had collected down in the hole where the spark plug and it's boot go and that lead to the corrosion issue. You can't "fix" it, you just need to clean the corrosion out of the coil pack connections as part of your regular maintenance. Like my 5.4L that's the only issue you will likely ever have with this engine.
But the coil-on-plug thing was the tipping point in ordering the 7.3 for me.
If it has plug wires like the OP's pic shows, then it can't be coil on plug, has to be coil near plug, right?
7.3 is configured that way too, right?
I am betting you have a coil pack that needs refreshing and is arcing to the block, as mentioned by TDog it will click/tick/snap and you can usually see it in the dark. I just went through this with mine, were arcing out of the coil pack stem.. You can buy the new AC Delco guts for them for 10 bucks a kit online. New resistor, wire and boot. I posted about it here which may be helpful if that's the issue. I bought a new coil pack for each side(they are left and right mounting) and took one out at a time and refreshed them with the kits. Swap the coil pack and see if the code moves. Also worth noting, I changed the first one and almost instantly one on the other side of the engine started doing it.
If it has plug wires like the OP's pic shows, then it can't be coil on plug, has to be coil near plug, right?
7.3 is configured that way too, right?
The 6.2L has 16 plugs, obviously 2 per cylinder. The upper plug is a coil-on-plug very much like the 5.4L, and moisture gets into the well where the upper plug lives. The coil pack has a second port that runs a rather ordinary spark plug wire to the lower plug and that's what you see in the OP's picture. The wire should be relocated a bit to stop the rubbing. I don't think I'd bother replacing it.
The 7.3L has one coil pack per cylinder, 8 plugs total. The coil packs sit on little brackets on the valve cover away from a lot of heat and can't trap moisture. The only thing unique about the 7.3L spark plug wires are the little heat shields near the plugs. The wires are about a foot long each and all alike so "coil near plug" would be a way to describe it.
