[Paully33]

Ok my fuel indication problem is driving me flippin nuts!!! Ok so this is the story, OEM gas gauge was acting funky, fill it up, drive home 2 miles and shut off truck, get in it again to leave and gauge would be reading like 3/4 of a tank. Then drive a few more miles, shut it off. Leave again and it reads either high or low from last reading. This is what I did to start:

1. Pulled sending unit connector off and shot it with a meter, OEM gauge PEGGED out past full.--OK
2. Bought a new sending unit and pig tail connection from JBG and installed sending unit--Same problemo
3. Bought a Autometer Sport Comp Fuel Gauge (3315)(73Ωs Empty / 8-12Ωs Full)
4. Installed gauge and wired it up and used sending unit pig tail connector from JBG--OK
5. Filled tank up to the neck--OK gauge does not read completey Full in between 3/4 and Full---WTH?

So I double checked my grounds and connections everything was good.
Is it possible that I got a crappy sending unit or what? I am STUMPED!!

Anyone have ideas?

Paul

 

[Ranger429]

Check the wire running along the frame rail for a break or grounding out. A loss of voltage will throw off the reading.

 

[Paully33]

k. So if there is nothing wrong with wire could it possibly be sending unit?

 

[Ranger429]

Sure it could. Drop the tank and pull the sender out again and read the meter as you manually adjust the float level, see if it is working properly that way.

 

[bronco_kid78]

wiring has a lot to do with it. My ground got messed up and I had tons of problems. There still must be a small break in mine because on occasion my tank will fill itself up while I'm driving lol Then it usually returns to normal

 

[Paully33]

meter you referring to my ohm meter or the fuel gauge?

 

[Ranger429]

Ohm meter. If your using two different gauges, the stock and an aftermarket, it is not a gauge problem.

 

[Paully33]

no just using aftermarket one

 

[Joseph]

and like on a tps sensor it helps to have an analog gauge so you see rapidly the needle on the meter drop if there is a problem with it. just like to add that, but ranger is right on the money(as usual).

 

[Ranger429]

no just using aftermarket one

But you had the problem before the aftermarket gauge as well right?

 

[Mikes79Bronco]

But you had the problem before the aftermarket gauge as well right?

By reading his first post i would say yes...

 

[Ranger429]

By reading his first post i would say yes...

That is what I was pointing out.:thumbup

 

[Mikes79Bronco]

That is what I was pointing out.:thumbup

:beer

 

[Paully33]

yeah I did. So I will check as you said Ranger and re-check my wires

 

[1978custom]

you filled it up to the neck, and it reads 3/4 of a tank. if you drive/run some gas out does it read full? mine use to fill to e. i had to bend the float arm alittle. before i replaced the sending unit my float just got hung up, at diffrent places. kinda like you said. thought it might help.

 

[Paully33]

Ok I went out there this morning and checked my wires ground wires good powere wires good both from gauge to 12V source and gauge to sending unit. Checked the grounds agian, Ground on sending unit good. Ground for gauge lighting good. Ground for gauge good. Hit it with the ohm meter at gauge first 9.5 ohms, at sending unit pigtail power wire 9.5 ohms seems good to me ...(HA!) rechecked ground wire for gauge @ gauge disconnected it and gauge pegs out past full...good. Re connected ground wire and BLAH!!! nothing deader than a door nail. No reading on gauge what so ever. Check volts got good volts coming in and going out. Pulled new sending unit pigtail off and put OEM one back on, everything works. Kinda thinking I killed the gauge when I disconnected ground.

What do you guys think?

 

[Ranger429]

So it works OK now?

I suppose a small electrical spike could ruin the gauge.

 

[Paully33]

Ok I think I figured it out. Found my power problem, forgot I had a inline fuse to my sescondary fuse panel and course blew the fuse. So I fixed that then checked the OEM gauge agian reading 3/4 full.

So I hooked up the the Autometer gauge and checked it it was just shy of 3/4 full. So right there since it was close to the OEM gauge reading I was thinking sending unit. For $h!ts and giggles went and threw couple of bucks in gas in to see if it would take any more. Took like 3.5/4 gallons and the gauge reads past full now.

So gonna leave for a few days and watch it and see. Still leaning towards getting a new sending unit. The only thing I do not like about that gauge is you can see the needle moving around when the gas is sloshing around in tank. Might just go to junkyard get a new tank order a sending unit and buy a sump as well and hook it all up.