Hollabakzach23

^^X2 this could be helpful for someone in the future!

Motelec MotorSport

The problem was with the spark plugs and injectors, the trucks was running on sp514 that is for use on another 5.4 v8 engines like navigator, not the f150 5.4 v8 engines <07 . When the truck is on indle the LTFT dont work, and looks all is good, the problem was when the truck is on high load, the LTFT was crazy to 1.29, "very high" but only the bank 2 "i think some injectors was bad". I removed plugs and fitted the correct sp515, with nickel, new fuel filter and air filter, and send to a injector laboratory to check and clean the injectors, all injectors was bad, very dirty and leaking. Now the trucks runs like new, on highway i can see average of 18-19 MPG without problems , and in full street with a very bad traffic 13-14MPG. Now the trucks feels good and the problems with the transmission hesitation and jerks was out also, looks the problem with jerks and hesitation was the spark plugs that cause a bad combustion and detonations and feels like transmission problems.

SCT livewire was very good tool to find the problem, now i will go to the "garage" that changed the old plugs and do the maintenance filters, clean by two times the injectors etc, when i removed the filters looks like never was changed and no original parts was used in filters, and the fuel injectors newer was cleaned. But my invoce show, Fuel and air filters changed and fuel injectors cleaned "two times" , and new "NGK" plugs , when the plugs was Motorcraft sp514 which in any case are not correct and looks old.

Best Regards.