Fuel too lean on bank 2 on 1999 ford f150 6 cyl. 4.2

SOURCE: Ford Windstar 1996 Trouble Codes P0171, P0141, P0161, and P0174

Bank one is toward the front of the vehicle. Sounds like the heated oxygen sensors have gone bad. The Oxygen Sensors are located in the exhaust pipe and require a special socket to remove and replace.

SOURCE: bank 1 and 2 running lean on computer scan po171,po174

Doubt it.
It would be highly unlikely for both O2 sensors to go bad. I strongly suspect they are reading what is actually happening,the engine is running lean. Probably from some un-metered air getting into the engine either from a vacuum leak or from a leak somewhere on the engine side of the mass air flow sensor. What usually causes a concern on this vehicle is the orings between the upper and lower intake manifold.

SOURCE: My Navigator is running lean in bank 1 and 2 how repair myself?

On your Navigator the most likely failure that will cause a lean condition on both banks is the PCV tubing. Start at the PCV valve in the passenger side valve cover and follow it to its connection to the intake manifold, and closely inspect the rubber elbows in the tubing for vacuum leaks.

SOURCE: check engine light flashing runs rough not firing on all cylinder

take of the fuel filter and blow it out. i had the same problem with a 2008 ford f150 5.4 v8.

SOURCE: Q Where is the Bank 2 Sensor 2 oxygen sensor

Hello j_abell: My name is Roger and I will help you. Bank two sensor 2 will be on the drivers side of the engine. Second sensor back. behind the catalytic converter. Bank one sensor one would be on the passenger side of the motor. See attached picture.Should you need further help please just ask. Please rate the answer. This way I know it was helpful. Thank You for using Fix Ya. Roger