Miss fire issue

[2000 roush]

OK I got a 2000 Excursion with the V10 and it has been having issues with miss fires on number 1 and 6. replace both coils and spark plugs and now the soft code is saying there is a lean condition and a miss fire on 1 and 6. I also replaced the fuel filter, and filled up with Kwik Trip premium. Anyone have any ideas, this thing is starting to piss me off. I replace the coils with ones from my Roush and the car ran fine. It seems like every time I replace a coil and a plug it runs fine for about 10 miles. Checked the wiring and that seemed fine as well.

[Chrm97PI]

intake gaskets? whats telling you its lean, do you get a p0171 and p0174?

[2000 roush]

intake gaskets? whats telling you its lean, do you get a p0171 and p0174?

I think it was a p0174 and p0171. I am going to clean the Mass tomorrow and see what that does. I pulled the number 6 plug and it was wet so I replaced it with a new plug and another known good coil and let see what that does. Oh I also noticed the breather bung was broken off the left valve cover so I fixed that as well. It was the one tube that goes from the drives valve cover to the throttle body intake tube.

[POOPY PANTS FACE]

Try cleaning the MAF, is the filter stock?

[2000 roush]

Try cleaning the MAF, is the filter stock?

No I think it has a stock replacement K&N

[POOPY PANTS FACE]

No I think it has a stock replacement K&N

That could be the problem then.

[2000 roush]

That could be the problem then.

But I dont understand the miss fire issue, or do you mean the lean code and not the miss fire?

[POOPY PANTS FACE]

But I dont understand the miss fire issue, or do you mean the lean code and not the miss fire?

Could be both. Maf's are picky.

[2000 roush]

Cool thanks for the tip, Ill check it out tomorrow

[Sweet35th]

If it is missfiring, that is what is likely what is causing your lean codes. Are you getting a P0301 and P0306, or are you getting P0351 and P0356? Also you may actually only have 1 missfire. Cylinders # 1 and #6 are right next to each other in the firing order.. One could cause the other to trip a false missfire. If you were to swing by some time I can probably do a quicky cylinder ballance test for you to see what cylinder (possibly both) is missfiring. .

[2000 roush]

If it is missfiring, that is what is likely what is causing your lean codes. Are you getting a P0301 and P0306, or are you getting P0351 and P0356? Also you may actually only have 1 missfire. Cylinders # 1 and #6 are right next to each other in the firing order.. One could cause the other to trip a false missfire. If you were to swing by some time I can probably do a quicky cylinder ballance test for you to see what cylinder (possibly both) is missfiring. .

Where would be a good place to meet up to have you scan it? The codes i have are p0301 and p0306

[68GTO]

Who is this Miss Fire? Is she like Miss Car Craft?

[2000 roush]

replace 2 coils again and new plugs, found the nipple on the drivers side valve cover was broken off, fixed that and runs like a champ now. Even managed to pull 13.5 mpg up to Buffalo and back.