I just bought a used 90 s10 blazer. The previous owner just replaced the fuel pump and the gas gauge does not work. I see it could be the Fuel tank sending unit but if they just replaced pump, I ws wondering if something did not get connected?

 

The older trucks are not like the newer ones where the pump is an entire assembly including the fuel level sending unit. It is possible to only replace the pump and not replace the sending unit.

 

Okay, Do you still have to drop the tank in order to replace the sending unit? Are there any directions anywhere on how to do this?

 

Yes, you still have to drop the tank. As far as directions, I do not believe that anyone had done a writeup for this, at least not here.