AK907

Recently started having problems with my truck where the exhaust will start sputtering after driving around for a mile. Doesn't matter what speed it's at, the truck will start sounding like a chopper. Getting up to 50-55, it starts shaking. Connected it to a machine at O'reilly and it just said Misfire on Cylinder #4. Replaced the spark plug and tried a new air filter, but those weren't an issue. Guess I could try a new fuel filter, but anyone know what else it could be? 4.6l by the way.

treiljr

You may want to check into your coils on plugs (COPS) if you have them. There is alot of info on this forum if you search. I am currently having some issues with what I believe are one or more of my COPS. I'm saving up the money to purchase them. I here there are deals on Ebay with a company called Global. Or you can always buy Motorcraft! Good Luck!

aerosurfer

ditto,

Had this problem when I bought my truck about 4 years ago. It was a COP misfire. I replaced it with an Ebay one, used at that too. Cant remember which one, and havent had any problems since.

Jawsh

Odd timing, I've got a misfire on #4 as well. I replaced the wires and checked the coil packs (Just replaced them for a tune up anyway, didn't get to spark plugs till now). I must have a rust deposit on #4 because I can't get the socket to engage the hex, plus, using the coat hanger scraping trick, brought up some rust flakes (Probably from the heater line drip problem). I've tried every trick in the book, so the Stealership is gonna be having some fun. Plus my hands are just too big to get in there well, so I'll let one of the munchkins at the dealer take care of #4 and #8 (Took care of the other six today). I have yet to meet someone working there that is anywhere near my size, so it should be easier for them.

On the subject of your issue, like stated, probably a COP or a wire. My brother actually had the COP on #4 crack and let water in and that caused a misfire for him. I'm glad I have Coil Packs, because it seems no one I know has a problem with their Coil Packs (Plus they're cheaper too), but the ones with COPs have the issues.

treiljr

Hey Jawsh, what can you tell me about running on a bad ignition coil. I just started having a problem about a 10 days ago and am trying to work up the money to replace. I read a thread about someone cleaning the cops up real well with gasoline, then they worked fine. My truck was on a ranch for most of its life and had quite a build up of dust and dirt in the engine. I have cleaned it up some but there is alot of dirt still around the plugs and cops. I am just worried about causing more damage until I can fix the issue, but a man has to get to work! Just yesterday I did a fuse check (compartment panel and power distribution box) and replaced the cigar lighter/data link connector fuse. I am headed to nearest auto parts store at lunch to get an OBDII check ran. My port inside the cab was not working. Should be good to go now. I would like to see if I can isolate the problem instead of buying 8 new COPS, although I saw a new set by Global on Ebay for $80.00.

Jekaldahl

My truck was missing on number 4 last week but I've had the truck almost a year and everytime I get a miss fire it's on that plug but I have new plugs, fuel filter, air filter, and new coil packs but when I went and looked at it earlier this week my boot fell off and I had moisture down in the hole

Jawsh

To be honest, I know very little about COPs, most of the stuff I do know about them is just from hearing about stuff that happened to people I know. Sorry I can't be much help, but I'm sure someone will chime in with an answer for ya.