How do you ohm out the TPS to make sure there are no breakages in the wires? And useing just a standard multimeter can you test the voltage to make sure its right? and how do you do it? (96 blazer 4.3 vortec) Thanks

 

I have always back probed the connections and read the voltage between the ground and the output to the PCM. Should be ~0.5V at closed throttle and ~4.5V at open throttle with no drop outs.

 

does the engine have to be running to test it?

 

No, the sensor has 5V going to it with the key in the run position without starting it.

 

okay well i have the 5v with the key on engine not running to the plug yet im still getting the p0122 code?

 

One wire will have 5 volts, one will be a ground, one will vary between half a volt and four and a half when you move the TPS. With one side of your voltmeter hooked to ground and other side hooked to the variable one move the TPS up & down slowly. Make sure the range hi/lo is right and it varies smoothly, no jumps or dropouts