I bought a 97 F150 that sat for like 3 yrs. I have been fixing little issues here and there. I have a couple of issues that I have not been able to figure out. When I turn the key to the on position my temperature gauge pigs out too hot. I’ve tried unplugging the temperature sensor and turning the key back on. It’s still pegs out to hot not sure what to do at this point. Also I have a 4 Wheel Drive with the shifter on the floor. The shifter is froze up and will not shift into four-wheel-drive or anything else. Any help that can be given would be eternally grateful.
Thank You, Tiny

 

Does it stay pegged to Hot when the engine is running? Do all the other gauges behave normally?

I would get underneath and spray the shifter linkage down with PB Blaster, repeating as necessary till the lever moves.

 

You turn the key to on position and the gauge slams to hot and stays there. Whether it’s hooked to the temp sensor or not

 

Does it stay there when the engine starts?

 

It doesn’t matter whether it’s running or not running. It doesn’t matter whether it’s first thing in the morning or after it’s been running all day. When you turn the key to the on position the temp gauge slams to hot and stays there. All the other Gauges appear to be working normally.

 

Are you disconnecting the correct sender? I believe there are 2 of them - one for the gauge, and one for the PCM. I don't know which way it should peg out when disconnected or whether the gauge should move if you ground the lead.

You may just have a bad sender.

 

The temperature sending unit that I replaced is the sending unit on top of the intake manifold