I have a 2001 Ford f150 V6 4.2. I have bolt P0171 or P0174 Lean Code, cleaned the fuel injectors, new MAF, and new manifold gaskets, still no help. Any thoughts?
Thursday, February 13th, 2014 AT 11:45 AM
Check fuel pressure with a gauge probably low auto parts rent them.
Thursday, February 13th, 2014 AT 11:57 AM
Fuel pressure is right where it needs to be. Maybe when I put in a new fuel filter some air got in the line and gave it the code again?
Sunday, February 16th, 2014 AT 2:54 PM
No that wouldn't happen with the air here are a few tips from tips page that
other shops have found an d may be your cause.
. Replace the isolator bolts holding the middle intake down. Just had the same truck and condition. Can see with the scannner showing upstream O2 pid, spray carb cleaner at lower to middle intake, and watch pid go to rich. Good Luck! Bolts $6.00 each at ford.
Either the 90 degree elbow for the P.S. Pcv hose (under the throttle body kinda hard to get to but you still can) or lower intake gaskets. Fel pro sells an updated kit for this. Also check this pcv elbow for sure as well as any grommet for holes in them as that wil do the same thing.