sysman_rick

Pack may be breaking down under load.

Jbrew

Honestly idunno lol - The quickest way to figure it out is on the dyno - 2nd is to tap into the Keep Alive Memory (KAM) after it happends.. 3rd = Mode 6.

Sounds electrical to me, maybe your fuel relay is playing games or the pump as you suggest. My guess is that your on the right track.

You don't have "packs" so scratch that one..You have COP's - Your problem doesn't follow COP characteristic failures..

Rwatson22

I just had a similar problem. I had check engine light come on, I noticed my fuel mileage dropped. The engine light went off so I kept driving it but a week later it started to miss and the trouble light came back on. The exhaust smelled bad. It was the #7 injector. It was going out and took a bit until it went out. Replaced it and it runs great.

john141456

Thanks for the advice! I replaced the coil pack and the sark plug in the 7th cylinder where the miss was... still happening. I am wondering if I have to go the injector route... was hoping this was not the case! I have a 98 4.6L 4x4. Was told that it can be a clogged EGR as well. Any other info would be very helpful. Thanks!

john141456

Bump! Help anyone!

mustanger1986

[quote=Jbrew;3085]Global Automotive out of Florida sells F150 kits 8 COPs and 8 new Motorcraft plugs for $130 quote]

You must be talking about Plugs and Coil Boots not the whole coil cause if they are selling motorcraft plugs and motorcraft Entire Coils for $130 Im bout to order a **** load and make some mad money cause those coils are at least 90-100 bucks a peice by themselves at the dealer.

John where the hell did you come from talk about hijacking a thread jesus man just jump right in why dont you. Yeah you might have an injector problem, pcm, or base engine concern have you ever worked on a mod motor before. Might want to take it to the dealership and let a professional help you out buddy sounds like your wasting yours or somebodys money throwing parts at that truck.

101stmp

to add to the confusion the other day when it hit like 0 here in upstate ny i went outside started my 00 f150 with the 4.6 in it when i statred it made like pop sound and died i then ran the codes which came u as p306 and p308 i bought 2 new cop (coil over plug) and the number 8 cyl cleared but the number 6 cyl is still missfiring if i unhook coil pack its worse than if i leave it hooked up as it sort of works .today im gonna change the plug and see what happends and if that dont work it will be a trip to the ford dealer to see what wrong.

lvlik9

I have a 2004 f150 4.2 v6...got a ramdom misfired code, misfired on 4,5,6, misfired on start up....lean code on bank one....runs rough at idle and regular driving don't matter what speed or rpm...change the coil pack, plugs,wires, fuel filter(a year ago), check the fuel pressure and it was at 34 psi, plugs and wire are motorcraft and coil pack Is from autozone, its not my truck, just working on it for a friend...any ideas someone before I go changing parts for nothing...

SuzukiRider

You have misses on one entire side of the engine so its not going to be anything directly connected to one cylinder. You are running lean on the left bank so Im guessing you have a vacuum leak, probably a cracked intake manifold gasket. Spray water around the left side of the engine and see if the truck chokes, that will find your leak.