Hey guys. I'm new to this forum. Been reading a lot to try and figure out my issue but couldn't find anything. I have a 97 f150 4.6. I was driving one day and it just started misfiring. Ran the codes and it was cylinder 4. Pulled the plug and the center wire was missing and the ground post was almost melted completely off. Replaced that plug and all the wires and both coil packs. Checked the other plugs and they were fine. Didn't do any good. I just spent almost 2k replacing the entire fuel system and the ball joints and tire rods and so forth. I do not really have the money to just keep throwing at it. I still drive it short distances and now I am getting cyl 3 4 7 and 8 misfire. Runs terrible and I can't drive it. Does anyone have a clue as to what the issue could be. Thanks

 

Also the cyl 1234 side ticks

 

2-4-7-8 all share the same coil............might check coil and connections ?

 

Thanks for the reply. I bought both new Napa premium coils and Napa wires along with all new Bosch platinum plugs and connections are good and getting 12+ volts

 

Also that is similar but the left coil is 2 4 7 8. Ground issue or something electrical? Maybe a PCM I was told possibly?

 

A) Bosch plugs are much less good than Motorcraft plugs for this application. Use Motorcraft spark plugs.

B) Just because you threw new parts at it does not mean the new parts are good parts. You could have a bad coil brand new out of the box. Or bad fuel injector, or bad fuel injector wires, bad fuel pump, etc.

C) Misfires specifically on 3 4 7 & 8 suggests to me the possibility of water leakage either dripping rain from the cowl or leaking heater hoses into the spark plug holes. Water will not magically evaporate out of the spark plug holes and will cause misfires. If that is the case, compressed air should be used to blow dry the water out of the spark plug holes and boots.
However, the damage to the plug on #4 may have sent shrapnel banging around to damage the hard parts. If that is the case, no amount of top end bolt on parts swapping is going to help and at the very least the head will need to be removed to repair.
Also make absolutely certain the plug wires are connected correctly and dry at both ends and that they are routed so that they do not get burnt, cut, or pinched in normal vehicle operation.

D) Ticking on one side but not the other may be leaking exhaust from the famous broken exhaust stud issue or damage from the shrapnel mentioned in C above or other cam or valve issues.

 

I apologize for the misinformation. They are motorcraft platinums. I always install OE