The 2.2L or the 4.3L engine?
The temp sending unit may be shorted to ground. Unplug the sending unit to see if the gauge drops to cold. If it does, you have a faulty temp sending unit.
Do you mean the Temp sending unit, oil pressure sending unit, or fuel level sending unit?
Which sending unit? Oil pressure sending unit? Engine temp sending unit? Fuel gauge sending unit?
A faulty temp sending unit can do that.
Where is the oil pressure sending unit on 1992 ford ranger
If the wiring and connections at the coolant temp sending unit check okay start with replacing the coolant temp sending unit. Temp sending unit should be less than $20.
On the passenger side, way back, under the exhaust manifold.
What sending unit are you looking for ? Fuel , oil pressure , water temp ?
The temp sending unit should be found close to the thermostat housing. It will have a single wire attached to it.
To fix the temp gauge check the temp sending unit first. A bad sending unit is a common problem with the temp system.
The temp sending unit on a 1992 Ford 4.9 inline six engine is located on the passenger side of the cylinder head, way in back. It's hard to see.