p0302 cylinder 2 misfire

[Tony Crowder]

Hello,
I just purchased an '06 expedition back in January. I noticed that the engine stumbled between 45 & 60 mph shortly after I purchased it. A friend of mine said it needed new spark plugs probably. I took it to the dealer and they changed all the plugs ($400?) The vehicle ran great for 3 weeks. Then my wife took it to the store, then the CEL came on. I hooked up my obd reader and found the p0302 code. I had the vehicle towed back to the dealer, and now they tell me that they need to tear the engine down?? A rocker roller broke off possibly? ($1500 job?) I said I can't afford that and I had the vehicle towed home. Has anyone heard of this before? The dealer said they swapped cop's and plugs between other cylinders, but didn't do a compression test? Any info would be appreciated...thanks!

 

[06 Eddie]

I'm guessing the vehicle broke down or ran terrible and you had it towed? Didn't mention a break down in the above. I had similar problems with sputtering and no power on demand. Myself I did COPs and it helped a tad. Then it fell on it's face again and I ended up needing plugs and a fuel filter. Old filter poured disgusting black fluid out of it. It was suspected I wasn't getting enough fuel causing my misfire codes in cylinder 1. Now it runs like a champ. Have your fuel system checked make sure you are getting enough pressure and also check vacuum.

 

[Tony Crowder]

Thanks 06 Eddie,
Yes it did breakdown and I had it towed. Once the weather breaks here soon in Michigan, I'll be checking out the fuel filter, cop's, wiring and plugs again. I just bought the vehicle this year in January for $6K! It has 150K, in great shape inside and out (considering Michigan salt) I just sank $2K in it with new tires, suspension and ball joints? Now the nasty misfire! Ugh!

 

[Trainmaster]

Considering a misfire to be a broken rocker is quite a stretch. Do just what Eddie said. Treat it like you'd treat any miss. Coils, injector, etc. Don't even think of tearing down that engine without a compression test. Cylinder #2? You're lucky. It's all easy.

If it's too cold there find a good private shop. Should be no problem.

 

[1955moose]

I agree, you never tear into an engine until you diagnose and repair any electrical/ fuel issues that can possibly cause stumble, or misfire. 2005 and 2006 have a fuel pump driver module mounted near the spare tire, that causes all kinds of driveability issues. They get all corroded, and rusty. Might want to give a look see, and check out as one of your diagnostic points, while under there.

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