I have a 2001 f150 xlt and it has this miss that we cannot figure out. I have repalced all the coilpacks when we put in the new motor. I also put some new ngk plugs in at the same time. Ran great for a day then back to crap. We hooked a scanner up to it and got a o2 sensor 1 bank 1 code, a fuel system lean code and a random cylinder misfire code. So I went to the junkyard and grabbed the mass air meter out of the truck I got the motor out of it only had 42k on it and stuck it in truck ran great for about and hour then back again. We replaced the o2 sensor nothin still runs like crap. It has a serious miss when it shifts into overdrive and is running at crusing speeds,if you turn overdrive off it doesn't miss anymore. My only other thought is a PCM. We checked the EGR its working fine injectors are pulsing fine. I am at a loss and getting very frustrated. Does anyone know where the pcm is on a 2001 f150 I am goint to go to the junkyard and yank the one out of my 40k donar truck. Any other sugestions or advice would be appriciated. Thanks by the way it ran just like this with the last motor in it also

 

Im having the same problem!! Check out my thread for the full explanation. Ill be keeping frequent on this one good luck let us know

 

Its possible that you got a bad c.o.p. And the pcm out of the donor truck more than likely wont work with your truck, because they would need to have pretty much all of the same options like power windows ect... Anyway you would have to have it reflashed anyway. Hope this helps, and good luck.

 

Not knowing what else was changed during engine swap, but hearing the same condition existed with first engine and only missed while in OD, am asking myself, why? Sensor on trans? Was engine harness changed from original engine to present? I think looking towards common items, is in order.

 

for myself now know an egr malfunction is what was causing what I thought to be a missfire. The egr would open up too much going to part throttle and make the motor run like crap. I disconnected and plugged the egr vac line and no lugging at or deceleration clunk. Need a permanent fix still lol

 

Where is the egr vac line on these truckz, my trucks got a funny miss too and i would like to try and see if thats my problem too. Is it ok to run it for a while with that line disconnected?

 

the egr is located on the driver exhaust manifold. And if you follow the egr tube it will lead to the valve where you can unhook the vacuum connection. You won't damage anything by plugging the vac hose but expect a check engine light and lesser fuel economy.