Hi Scotty, I have a 2003 Ford F150 4.2 L V6. It has 200,000 miles on it. Ever since I have on this truck the check engine light has been on probably for the last 12 years. The check engine code is P0171 and P0174 which is bank 1 and bank 2 system is running lean. At 194,000 miles on the truck I had to get their engine rebuilt but it was not because of them codes. I have recently been trying to fix it I have had the intake gaskets replaced they coils and spark plugs replace I have had the mass airflow sensor and the two O2 upstream sensors replaced. I have took carb cleaner and brake cleaner a couple of times around to look for a vacuum leaks as well and have not been able to find one. Some people have told me it could be the PCV valve or there could be a leak on A hose on the back of the intake and some people have said that I might have a bad fuel pump. The truck runs great there is no complications with the way it performs though. If you could tell me any advice on what it could be that would be much appreciated. Thank you.
if it runs okay who cares mine are vacuum leaves can do that low fuel pressure can do that from a weak pump or a bad fuel pressure regulator but if it's a serious problem it would run bad and you said you've had that problem for years so me I say hack with it just drive it that way
