Misfire #2: At the dealership

[00blackgt]

Ok guys, I have been a lurker but now I joined the community because I need some help.

Ok so I own a 2007 Expedition EB as a DD. 100% stock. I bought it with 74k miles and all service records.

After i got it i took it upto NY where i noticed random misfires. I changed the plugs and it was fine. Then 5k miles later i had a misfire on number 6, so i changed that ignition coil. It was then ok.

Well now I am at 87k miles and last weekend i got a bad misfire (vehicle shaking) and I read the code to see there was a misfire on #2, so i changed the coil... twice... and the issue persisted. I then changed the 10k mile plug in #2 just to see. The problem continued, so off to the dealer the thing went.

They did the normal, moving the coil plug and injector around nothing. Then they wanted to pull the head, they assumed a burnt valve. But nope they are now stumped also. It is going back together today, any ideas?

thanks

Zach

 

[rburch]

I think im having the same issues! Im waiting for my taxes so I can take it in! Ive got a warranty but it doesnt cover anything electrical! So ill have to take it in and have them look at it and hopefuly it will only cost me my 100 dollar deductible!

 

[FordandPolaris]

Did you check all the wiring to the COP on that cylinder? That is the only other cause that comes to mind. Although I would think the stealership would have looked at that... Never know though. Trace the wiring and see if you can find any cracks etc.

 

[alaskanexpy]

could be a injector issue also.