1998 Lincoln Navigator

Other Category problem
1998 Lincoln Navigator V8 Four Wheel Drive Automatic 129000 miles

my check engine light came on, I took it to a friend and scaned it bank1 and bank2 came on the screen it said fuel was to rich so someone told me that one of his cars did the same thing and that it was the fuel tank pressure sensor so I bought it already but am not sure if it is the right part I haven't install it yet, my Navigator is using a lot of gas a lot so do you think that could be the problem or is it the fuel pressure regulator, please get back to me soon I do not want to pay double for repairs thanks Margarita. This are the codes
P 1131 Ho2 511 Lean
P 1151 Ho2 521 Lean
PO 171 System Bank 1 too lean
PO 174 System Bank 2 too Lean
December 4, 2007.

My opinion is to have a competent shop diagnose the problem as opposed to taking shots at the problem.
Testing can be done that will radically increase the likleyhood of correctly solving the problem.

Once a code is pulled there is a corresponding troubleshooting chart that can be followed to diagnose the reason for the light.

If you provide the code number I can provide the chart if your willing to do some testing. The testing may require some expensive diagnostic equipment however.

I doubt the fuel tank pressure sensor is affecting the fuel miliage. It will prevent the evaporative monitor from running and is part of the evaporative control system for emissions.

Dec 11, 2007.
The first thing I would do on this one is to clean the mass air flow sensor. The last two codes are very common for a maf that is contaminated, somtimes requiring replacement. Then clear the codes and see if any come back. The last two codes may be responsible for the first two.