i have a 07 screw with a 4.6l

check engine light came on two days ago again. so far i have tried cleaning the maf sensor, stp fuel system cleaner, and new fuel filter. when the code first came up, i would clear it out with my tuner and it would be back 3 days later. i put in the new fuel filter and now the cel comes on every 3 weeks. i checked for vac leaks, found none but put zipties on every vacuum connection under the hood just to be safe. i called troyer and they said its probably the o2s but they werent sure. since its only the left bank showing lean i figured i would take the left o2s and put them on the right and visa versa. if it was the o2s then the code should move from right to left. code just came back after the switch, still on the left so its not the o2s. i havent called troyer back.

anyways, my question is, if i put my stock tune back in, will the kam keep the code in it so i can put my stock tune back in and go to the dealer? its still under warrenty and im tired of dealing with this. i still have my stock intake, should i put that back on? if both banks were lean i would question the intake but its only the left.

any other home fixes i could try?

 

Can't offer any assistance to your question about the tune. The 02 sensor thing is different. I just posted a thread in the engine section about the PO402 code DPFE sensor. Check out the reply by Dirtbuster 1, its a lengthly entry, has a good report from a ford manual about the 02 sensors. Might help in your case.

 

just read it. it was very imformative but depressing as well since there can be a bunch of things wrong. guess ford can figure it out.

so that comes back to my original question, if i put the stock tune back in will the code still be there for ford to find when they do a scan?

 

If there is a issue and you do clear it, which you shouldn't using sct software, it will pop up for the dealer most likely.