FUel sending unit problem

[dookie]

So i am in the process of installing all of my new gauges , and i was checking for which wire was which on my factory plug , and just about had it all figured out , i had the new cluster laying in my lap , My fuel gauge was working correctly , but my tach would not , i got irritated with it all and pulled the whole thing out and took it back to the lab .. (the kitchen table ) , took the tach out to my car and got it figured out all by itself . Was pleased with this , so i took it back inside and reassembled it into my cluster and into my sea of wires ... took the whole thing out and just before pushing it all into its final resting place i decided to turn my ignition back on and just double check everything, now the tach is working fine , but my fuel gauge isnt doing anything . could i have somehow grounded the sending unit wire out and messed somthing up ? I cant find a blown fuse anywhere ....

Cliffs : i think i may have somehow grounded out my fuel sending unit wire, because now it wont work , it worked before i started changing out my gauges.... HELP!

73 z28 , and all autometer gauges...

[rwhite692]

Did you connect an ohmmeter between the sending unit wire and chassis ground, to see if there is continuity (or very low resistance) between the two?

[dookie]

No i have not , my main question is , is what could i have done from inside the car , to cause a problem ... when there never was one before..

[XcYZ]

If your gauge always reads empty, the guage is seeing 0 ohms between the gauge and chassis ground. 0 ohms is empty, 90+ ohms is full. Use an ohmeter to check the sending unit conductor for a short to ground.

[dookie]

check the semiconductor to ground ? where is that located , and like i mentioned could there have been anything that i could have done to cause this from the factory wiring harness coming out of the dash? I never had one ounce of trouble out of my stock gauge.

[XcYZ]

The conductor is the single wire that goes from the gauge to the sending unit. If it's shorted to chassis anywhere, it will read E al the time.

[dookie]

thanks guys for the input .
Note to self , when you get really aggravated , and all of the wires look like they have become the same color , and you cannot stop saying obsenitys, its time to go inside , and get some rest , and not worry about it until the next day.
' I came home this afternoon , took my test light out , found a bad fuse that i was going to use for my power wire that i thought i had blown , but the contacts were just not making contact because of the fact that they were almost 35 years old .
I could have sworn that i checked the power wire going to the fuel gauge on something else , but obviously not , when i fixed one , the other one majically fixed itself .......