Hello there. New guy to the forums here. I have a 97 f150 4.6l and the temp gauge stays maxed out. From what i can see both of the sensors next to the alternator are brand new. If i disconnect the plugs from both sensors the guage still stays maxed. Is the another sensor im missing somewhere? Thanks in advance

 

One sensor goes to the computer.
The other goes to the dash solid state device which drives the gage.
Either there is a short to ground on the sensor lead or the dash display has an issue.
To see this layout look at page 12-31 of a Haynes repair manual.
Good luck..