dead fuel gauge

[alm0263]

Ive got an 84 m1009 with a dead fuel gauge. I would like to buy an autometer gauge to replace it, has anyone done this before, and has some tips? does anyone know if the fuel sender is 0-90 ohm like the rest of the gm vehicles? or if it is something different? all help is greatly appreciated! thanks!

autometer sport comp 2 1/6 mechanical fuel level gauge is the one ive got my eye on

 

[doghead]

You had better test your sending unit, it may be your problem. Have you looked in the TM for the test procedure and specs?

 

[HAWKMAN]

Get a hose and clean off the top of the fuel tank you may find that your ground has rusted off causing the dead gauge. My worth

 

[NJCOP35]

I can't get my gauge to go past 1/4 tank with a full tank, but once I run it down it starts working form 1/4 tank to empty? any ideas on that one? could it be the ground also? any ideas?

 

[ida34]

Sending unit. The fuel gauge is just a resistance meter. The sending unit is a variable resister. Yours is not making contact above 1/4 tank. You can take it out and check the resistance in different positions. The manual procedure involves grounding the lead to the sending unit. The gauge should beg full and when disconnected it should go back to empty. I think the full resistance value is 200 ohm IIRC.

 

[NJCOP35]

Thanx for the info! Is it a pain to get out? should I just leave it alone?

 

[HAWKMAN]

To get to the sending unit you have to drop the tank which can be a handful if you have never done this before and you may also inadvertantly remove some rust that has been keeping the tank sealed causing a leak....I've had a couple trucks come in that had a panel cut in the cargo area to gain access to the unit but that's up to you. hope all works out for you

 

[GreenBull]

Testing the circuit is simple. The sending unit resistance is 0 ohms empty and 90 ohms full.

Disconnect the sending unit. Expected result with key on is gauge reads past full.

Probe circuit (gauge side) with a normal automotive test light. Expected result with key on is a light that is somewhat dimmer than full intensity and a gauge reading somewhere between full and empty. This will vary based on the test light used.

Ground the sending unit circuit (gauge side). Expected result with key on is a gauge reading empty.

If testing leads you to a gauge or circuit problem don't overlook corrosion or poor contact at the clusters printed circuit, harness terminals, or gauge posts as a cause.

Good luck