Author Topic: gas gauge stopped working  (Read 5747 times)

Offline Glennster

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gas gauge stopped working
« on: July 23, 2012 - 07:46:37 pm »
I checked the wire on the sending unit, it looks OK. It's still hooked up. I looked at the fuses, old eyes make it hard to see, but I think they are OK. I installed a new 3/8" sending unit last year.
 I do not have a Ralle dash.
Any ideas about what went bad?
Which fuse feeds the gauge?
THANKS!




Offline brads70

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Re: gas gauge stopped working
« Reply #1 on: July 23, 2012 - 07:53:55 pm »
try giving the ground strap a wiggle.
Brad
1970 Challenger 451stroker/4L60 auto OD
Barrie,Ontario,Canada
Proud to own one of the best cars ever made!!!!!

My restoration thread 
http://www.cuda-challenger.com/cc/index.php?topic=59072.0
 My handling upgrade post
http://www.cuda-challenger.com/cc/index.php?topic=73985.0

Offline Glennster

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Re: gas gauge stopped working
« Reply #2 on: July 23, 2012 - 08:56:20 pm »
I don't know what that is........
I did check the wire that hooks to the sending unit.

Offline Jamiez

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Re: gas gauge stopped working
« Reply #3 on: July 23, 2012 - 09:22:08 pm »
There's a strap from the tank to the body.  It provides the ground for the sending unit.  Corrosion tends to be an issue with this connection. Without a good ground connection, pretty much nothing works correctly

Offline brads70

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Re: gas gauge stopped working
« Reply #4 on: July 23, 2012 - 09:31:48 pm »
There's a strap from the tank to the body.  It provides the ground for the sending unit.  Corrosion tends to be an issue with this connection. Without a good ground connection, pretty much nothing works correctly


 :iagree:  ground strap connects from the steel fuel line on the body to the steel hard line on the sending unit.
Here is one.
http://www.rosevillemoparts.com/product_info.php/p/sending-unit-ground-strap-correct-length/products_id/4118
Brad
1970 Challenger 451stroker/4L60 auto OD
Barrie,Ontario,Canada
Proud to own one of the best cars ever made!!!!!

My restoration thread 
http://www.cuda-challenger.com/cc/index.php?topic=59072.0
 My handling upgrade post
http://www.cuda-challenger.com/cc/index.php?topic=73985.0

Offline BS CUDA

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Re: gas gauge stopped working
« Reply #5 on: July 24, 2012 - 12:01:57 am »
:iagree:  ground strap connects from the steel fuel line on the body to the steel hard line on the sending unit.
Here is one.
http://www.rosevillemoparts.com/product_info.php/p/sending-unit-ground-strap-correct-length/products_id/4118


 I actually soldered a 12 or 14 ga wire with eye to my ground strap on the sending unit and grounded it to the frame right beside the tank sending unit. I did this as I have removed the steel fuel lines and ran -8 braided line front to back and the strap wouldn't work on these new fuel lines. I have not had an issue with this ground and fuel gauge works perfectly.

Offline tman

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Re: gas gauge stopped working
« Reply #6 on: July 24, 2012 - 03:25:00 am »
My sending unit was bad when it always showed "Full."  After checking connections that were good, I changed the sending unit and guage worked good.  Where is your guage stuck at?  Sometimes the float arm gets stuck in a position. If guage and wiring is good, I tend to think the SU is bad, even though you changed it last year.  Even those floats go bad. 

Offline Jamiez

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Re: gas gauge stopped working
« Reply #7 on: July 24, 2012 - 06:03:59 am »
You can disconnect the lead from the sending unit and run various voltages into it, the needle should move somewhere between E and F based on the voltage.  That would isolate the problem to something with the sending unit (bad ground, bad float, stuck float, etc)

Offline Glennster

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Re: gas gauge stopped working
« Reply #8 on: July 24, 2012 - 07:35:54 am »
My gauge is stuck on empty.
I forgot about the little ground strap. After seeing the picture, I remember what and where it is. I'll take a look at the sucker this evening.
  We sell fuel systems to the RV Industry for the 5th Wheel Toy Haulers(and many other things, microwaves, sinks, faucets, bath tubs, showers, flooring, ect), I should have thought about testing the sending unit. We have a little 12v set up we use to check these.
Once again....... I THANK YOU guys for your time and efforts!

Offline kmyles

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Re: gas gauge stopped working
« Reply #9 on: July 24, 2012 - 11:20:46 am »
 :popcorn:
_________
Kevin



Mopar Lover....Cuda's....Challengers Rule!!!!
- 1951 Dodge - 2 door hardtop (Sold!!)
- 1971 Dodge Challenger
- 2012 Dodge Challenger Yellowjacket

Hard to believe what 20 years will do!!!!

Offline dodj

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Re: gas gauge stopped working
« Reply #10 on: July 24, 2012 - 11:50:13 am »
 :popcorn:   mmmmm..... don't you love cc.com popcorn ? :grinyes:
Scott
1973 Challenger  440 4 spd 
2007.5 3500 6.7 Cummins Diesel, Anarchy tuned.
Good friends don't let friends do stupid things. ........alone.

Offline Glennster

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Re: gas gauge stopped working
« Reply #11 on: July 24, 2012 - 09:45:52 pm »
I checked the ground strap. It looks like it'just where it should be. I can't post pictures, my computer is in the shop.
posting with my phone sucks....
I'd like to run a back up ground, do I just attach the wire. Anywhere on the sending unit and then hook it to the frame?

Offline dodj

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Re: gas gauge stopped working
« Reply #12 on: July 24, 2012 - 09:52:40 pm »
I don't think a back up is really needed, just check to make sure the first is in good shape - not corroded
Scott
1973 Challenger  440 4 spd 
2007.5 3500 6.7 Cummins Diesel, Anarchy tuned.
Good friends don't let friends do stupid things. ........alone.

Offline spamtank

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Re: gas gauge stopped working
« Reply #13 on: July 24, 2012 - 10:06:20 pm »
I don't think a back up is really needed, just check to make sure the first is in good shape - not corroded

Here's a basic question about the tank grounding.  Where is the intended ground path.

The tank is mounted to the body with the "tar paper pad" - no direct ground there.

The tank is held in with the metal straps and j-bolts - maybe that's the direct path to chassis.

The fill tube fits into a rubber grommet - no ground there.

The ground strap jumps across the rubber connecting hose on the fuel line, but then the fuel line runs under the car, and is clipped in place underneath, with lots of opportunity for corrosion and poor electrical contact to develop over a short time.  Furthermore, it snakes up to the engine bay, where there is a fuel filter attached with two rubber hoses, so there's no ground path there.

I ask because I have the blinking low fuel light, and as I drive over wash board bumps, there appears to be a vibration induced fluctuation of that light on and off.  I did paint my tank and straps with clear krylon.  Now I'm thinking that might not have been the best idea.

Inquiring minds want to know.....   :clueless: :clueless:

Thanks,
Rick, Manchester, NH
1970 SE 383 2V AT Challenger
1977 M882/W200 Power Wagon
2013 RT Plus 6M

Offline Barracudadan

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Re: gas gauge stopped working
« Reply #14 on: July 24, 2012 - 10:26:45 pm »
Here's a basic question about the tank grounding.  Where is the intended ground path.

The tank is mounted to the body with the "tar paper pad" - no direct ground there.

The tank is held in with the metal straps and j-bolts - maybe that's the direct path to chassis.

The fill tube fits into a rubber grommet - no ground there.

The ground strap jumps across the rubber connecting hose on the fuel line, but then the fuel line runs under the car, and is clipped in place underneath, with lots of opportunity for corrosion and poor electrical contact to develop over a short time.  Furthermore, it snakes up to the engine bay, where there is a fuel filter attached with two rubber hoses, so there's no ground path there.

I ask because I have the blinking low fuel light, and as I drive over wash board bumps, there appears to be a vibration induced fluctuation of that light on and off.  I did paint my tank and straps with clear krylon.  Now I'm thinking that might not have been the best idea.

Inquiring minds want to know.....   :clueless: :clueless:

Thanks,

I painted my tank and straps with a clear coat too no issues for me everything works fine, maybe corrosion on the contacts for the fuses in your fuse block? I have some corrosion there if my fuses don`t sit just right it causes my fuel gauge problems I put di-electric grease on the fuses seems to help improve the contact.