Oil sending unit is under intake manifold, just behind the oil filter on the passenger side (difficult to see-use flashlight). Best option to change : Get everything to do an oil change, removal of the filter makes easier access.
Assuming you mean the engine coolant temperature sending unit, we need to know what engine it has, it makes a difference.
how do you replace the fuel sending unit
In the fuel tank. Fuel tank must be removed to gain access to the sending unit.
In the fuel tank. The fuel tank needs to be removed to gain access to the sending unit.
The fuel tank has to be removed to gain access to the fuel sending unit. The fuel sending unit and the fuel pump is replaced as a unit.
The reading will vary from empty to full.
At the rearmost section of the engine to the right of the distributor.
Probably the sending unit inside the fuel tank is bad.
Could be a faulty temp sending unit.
There are actually two water temperature sending unit on a 1994 S10 Chevy. Please locate the unit close to the thermostat housing, and not the one between spark plugs. The single wire water temperature sending unit should then be attached to the temperature gauge. The two wire unit, the one between spark plugs, would be connected to the engine control module.
The 4.3 temp sending unit for the gauge is located in the drivers side head between spark plugs 3 & 5.
Locating on a 2000 s10 pickup truck: bronzer idea