How do i read my 91 ford explorer odometer?

You need to get an actual pressure test on the block to get an actual reading, because I would hate for you to have lubrication problems in the engine and blow the engine. If the gauge is stuck on zero try with the engine off and key on, ground the sending unit wire to the block and see if the gauge pegs to full. If it does not, replace the gauge and get it calibrated if it needs calibrating.

Did you try to reset it.

may just be a faulty sensor. or bad earth. how long ago had it been since it has had an oil change ?

You have timing chain, tensioner, and cam phaser problems. get out you wallet, its not cheap. Your FORD dealer will know what to do.

maybe change the oil

It sounds like your oil pump is going out. I have a 98 ford explore and I went through the same thing about a year ago. I changed the oil pump cleaned the screen and have been good everysince.

If you have the owners manual it will tell you. need more in fo. Is it a change oil soon lit or is ther a multi reset switch by the odometer?

Ford Explorer, Mercury Mountaineer, 2002-06

To reset CHANGE OIL SOON/OIL CHANGE REQUIRED message on the Message Center, press the SET UP control to access the System Check mode. Press and release the RESET button to display “OIL LIFE % HOLD RESET NEW” is displayed. Press and hold the RESET button for 2 seconds until “IF NEW OIL HOLD RESET” is displayed. Press and hold RESET button until “OIL LIFE SET TO 100%” is displayed.

Ford Five Hundred, Freestyle, Mercury Montego 2005-06 Tap the ODO/TRIP button to toggle the display between the odometer and trip odometer. Tap on the ODOiTRIP button again to toggle the display between the trip odometer and OIL LIFE % display. Press and hold the ODO/IRIP button for 2 seconds or more to display OIL LIFE 100%. Your oil life in now reset.
Good luck and print this and keep it in the glove box. Keep me posted if you have any other questions

Ford Explorer, Mercury Mountaineer, 2002-06

To reset CHANGE OIL SOON/OIL CHANGE REQUIRED message on the Message Center, press the SET UP control to access the System Check mode. Press and release the RESET button to display “OIL LIFE % HOLD RESET NEW” is displayed. Press and hold the RESET button for 2 seconds until “IF NEW OIL HOLD RESET” is displayed. Press and hold RESET button until “OIL LIFE SET TO 100%” is displayed.

Ford Five Hundred, Freestyle, Mercury Montego 2005-06 Tap the ODO/TRIP button to toggle the display between the odometer and trip odometer. Tap on the ODOiTRIP button again to toggle the display between the trip odometer and OIL LIFE % display. Press and hold the ODO/IRIP button for 2 seconds or more to display OIL LIFE 100%. Your oil life in now reset.

NEEDS A NEW INSTRUMENT CLUSTER