I took fuel sending unit out because it's not reading right. Found out the float arm was not attached to the voltage resistance thingy. It had come out of the two plastic clips that hold it together. I re-secured it made sure it was evacuating properly and then plugged it back in separated from the gas tank. It read 0 on the gauge in the car (I mean empty) no matter how I actuated it from full to empty the gauge shows empty. I plugged a new one it did the same thing. The frick??? I have power and ground because the old fuel pump turns on and runs. (Dont worry I have a new FP anyway. Am I missing something? Am I testing the float the wrong way? I just want to see it working before I put the gas tank back in and put fuel in...

 

I got it . I found some videos. It's either the sending unit or the gauge. Because the pump runs if it was the ground or the wiring the pump wouldn't run so it's either the unit or the gauge. Now, whether it was just the float arm out of place or not remains to be seen. I'll post what I find

 

Going to check for continuity between dash gauge and rear outside plug if I have continuity then I will check gauge

 

 

I checked the plug for power and ground and I do have it. I rechecked the sending unit and the ground on the wire harness on the unit and I'm good when the float moves. Now in the car with the sending unit connected I touch pins # 7&4 and then pins 12 &4 and wierd things happened.

I couldNt get a 0 reading nor a 90 reading. I got all kinds of strange #'s but then always returning back to 001 in the ohm reading. It got dark on me tonight but what I'm going to is connect a wire from the the dash purple to the purple at the plug near the rear and check for continuity. I can run a new wire if I have to. Oh, I check both of the gauge cluster grounds against the power and I am getting 12v. So that tells me that both of those grounds are ok pins 7 &12.. pin 4 is the only one that seems to be in question

 

Oh forgot to mention I connected the OEM gauge and moved the float and it would only go as far as .25 tank then back down to empty. This was with the key turned to the on position and after the unit was tested

 

Checked for continuity on ppl wire. - good
checked for ground - good
Checked for power 12v - good
ConnectEd new gauge - reads perfect
reconnected gauge cluster- reads empty

Diagnosis- bad gauge
Remedy - aftermarket gauge and keep on rolling
My cluster is practically useless now. But will keep it for the looks!!!
next- make v6 speedo work with usedtobe cable driven tranny , somehow!!!

 

Thanks thirdgen.org you all taught me how to do this!