hey guys first post here, have a 2007 4x4 5.4 Triton and not sure if it matters but it has the canam air flow system and a Edge performer, and at low RPM it has a weird feeling miss, some times so bad the transmission will start to shift in and out of high and low gear, when it gets that bad it pops a po452 code which i think is a result not cause.. any ideas please ??

 

You are running an aftermarket intake with a programmer with canned tunes? You are running excessively lean. Reload the stock tune, and you may even want to put the stock intake back on. If the spark plugs have more than 60k on them, change them.

 

Thanks for for the reply, and i have reloaded stock files and it still does it, but the crazy thing about it is that it don't do it all the time i can run it for two weeks sometimes with no problem and than out of the blue it will just start acting crazy again, i have even tried running the shell v power 93. and when i did it stopped acting up so i thought i solved the problem, but i let it get low on gas the other day and it started acting up again so im not sure if that has anything to do with it or not. is it possible that i have a tank with some trash in it and when i run it low on gas i push some into the filter??

 

When's the last time you changed that fuel filter?

 

never have and my bad its a K&N air raid air filter

 

Change it, it's easy and could solve your issue. They should be changed at least every 30k. I do my every 15k, a lot of others do as well.

 

yea its worth a try, does the fuel pressure change going though the filter depending on the amount of throttle i am giving it or does fuel pressure stay the same regardless ?

 

The fuel pressure is regulated by the FPDM. It's on the crossmember above the spare tire and is notorious for corrosion on the back side. The replacements have spacers to stand it off from the crossmember. If your OBD2 scanner is capable, it can monitor fuel pressure. That's the only way to test it, there's no test port for a gauge.

Those K&N filters are garbage. They don't filter worth a crap and the oil can foul the MAF sensor. Clean the sensor.

 

Another thing that i have noticed is it don't seem to act up as long as my heads are around 200F.