Issue with SUV dying when warmed up... PLEASE HELP

[GilGraue]

Ok so about a week ago we were driving my wife's expy. It's a 2002 EB 5.4L V8 Triton with approx. 170xxx miles. For the first 15-20 minutes of driving, it was fine. Once vehicle warmed up, it would start to sputter and then die out, especially when trying to go from a stop sign or red light turning green. Also, CEL was on and autozone got the codes P0171 (Fuel system too lean cylinder bank 1) and P0174 (Fuel system too lean cylinder bank 2). They also recommended replacing PCV. So far, I've replaced PCV valve, fuel filter and MAF sensor. Still having the same issue (runs fine for first few minutes then will sputter and then die, especially when trying to go from a dead stop). When this happens, I have to let it sit for about 30 minutes before it'll start and stay started and will drive for a few minutes before it happens again. Also, when this happens, it will sound like it's backfiring and/or starving right before it dies out. I am now being told it is the fuel pump, which I replaced about 4 years ago. Before I replace the fuel pump and strainer, I thought I'd come here and get some input from more experienced folks on this issue... Thanks in advance.

 

[1955moose]

Gil welcome to the forum. We get those two codes constantly around here. Before you change fuel pump, a few things I'd like you to do. 1, replace the rubber elbows and hose going to the pcv valve. They rot out and cause more headaches. Available at all auto parts stores. 2, buy a can of Maf sensor cleaner and spray the heck out of your sensor located under air filter tube. 3, spray out throttle body insides with throttle body spray. 4, have a fuel pressure test done, or maybe you can do it. The pressure, and more important the holding of said pressure will tell if pump, filter, and injectors are sound. Report back what you find, Moose.


Sent from my N9131 using Tapatalk