fuel guage goes way past full on M1009

[erniemigi]

Has anybody had an issue with the fuel guage going way past full, it does go back down as i use the fuel that is in there, i'm just wondering if they had allowed the right amount of reading on the guage for the M1009s since they do have a 27 gallon tank, i have never let it gone down past 1/2 tank, afraid that the guage or unit in the tank might be messed up

 

[NMC_EXP]

Has anybody had an issue with the fuel guage going way past full, it does go back down as i use the fuel that is in there, i'm just wondering if they had allowed the right amount of reading on the guage for the M1009s since they do have a 27 gallon tank, i have never let it gone down past 1/2 tank, afraid that the guage or unit in the tank might be messed up

There is a troubleshooting prodedure in the tech manual which is supposed to narrow the problem to the sending unit or the gage. But I've been too busy keeping the thing running to sweat the little stuff.

When mine is full the gage reads 3/8. With half a tank it reads 1/8.

I write down the mileage when I fill it and fill it again after 300 miles.

19 MPG x 27 gal tank = 513 mile cruising range.

(Thats 19 MPG when everything is working)

Regards

Jim

 

[Brent.Cain]

ya i had that problem and i pulled apart my dash and too apart the gauge cluster and cleaned every thing really good and put it back together and it all works just fine along with i took the time and bought all new dash lights

 

[M813rc]

When mine is full the gage reads 3/8. With half a tank it reads 1/8.

Interesting, one of mine indicates precisely the same way. Just started doing it recently. It was quite accurate before that.

Cheers

 

[91W350]

Both of mine go way past full, about 1/4 the width of the meter. It takes about 100 miles for the needle to start moving and another 50 to 75 miles to get down to "full" Glen

 

[erniemigi]

well i guess i know what else i am going to do next week, on top of a few other things, 1 is to find that horn relay, 2 is to replace the voltmeter relay, 3 is to replace the block heater, 4 replace the dash lights and to clean up the fuel gauge connections (mise well i will be in there anyways) 5 fix the windshield wiper/turn signal/ high beam switch (that one is driving me nuts, hit a bump hard enough and the high beams come on) well at least it will give me something to do, thanks everybody

 

[combatmech]

My fuel gauge has been pegged out since I bought it. My first 1009 would show full for a while then drop to half. I'm thinking my current problem is the sending unit.....who knows??!?!?! I too will be pulling the cluster soon. Maybe next week...

 

[cjtroutt]

I installed a NOS fuel sending unit in my M1009 it worked right after install the float end was about to fall apart.

 

[NMC_EXP]

Interesting, one of mine indicates precisely the same way. Just started doing it recently. It was quite accurate before that.

Cheers

FYI - I had a new sending unit installed before I was aware of the troubleshooting procedures. In my case, the new sending unit had no effect on gage accuracy.

Still have not run thru the troubleshooting process....too many other fires to fight.

Regards

Jim

 

[Warthog]

Alot of the times it is a broken wire between the sender and the gauge or a bad ground wire connection above the left rear tire..

The TM troubleshooting section helps you figure it out.

 

[NMC_EXP]

Alot of the times it is a broken wire between the sender and the gauge or a bad ground wire connection above the left rear tire..

The TM troubleshooting section helps you figure it out.

I'm hoping it is a bad ground but had not located it. Does the sending unit ground to the frame above the L.R. tire?

The electrical schematics are good to but diagrams on paper do not look like whats on the vehicle.

Thanks

Jim

 

[donalloy1]

mine does same thing. drops rapidly to half after 100 or so miles of driving. puts me at about 15-17 gals burned. thought it to be normal. guess i have another project?

 

[Warthog]

I'm hoping it is a bad ground but had not located it. Does the sending unit ground to the frame above the L.R. tire?

The electrical schematics are good to but diagrams on paper do not look like whats on the vehicle.

Thanks
Jim

Yes the sending unit ground to the top of the framerail above the left rear tire. A flashlight helps you see the sender and wires. You just can't get to the sender without removing the tank or cutting a whole in the rear floor.

 

[Timber]

If the needle moves down to E, it's reading correctly. This is my fourth Blazer and every single one of them went a good half inch past the F mark when filled up. And they stay there a bit. Within 100 miles after fill-up the needle will start moving toward the 1/2 mark, but it will stay pegged a couple of days. Once it makes it's way the the 1/2 full mark it heads toward E fairly quickly.

If that's what yours is doing, you have a properly functioning 73-87 fuel gauge.

Hope this helps.

 

[erniemigi]

almost afraid to let it drop down past 1/2, going to try the test from the TMs first and c what kind of results i get

 

[Gottlos]

Just got my cluster installed after replacing the fuel gauge. The needle was about a 1/4 to 1/2 inch past the full mark after refueling. I figure I'll wait till it gets to 1/2 then I'll refuel. Hopefully I will only pump 13 gallons! If not I'll at least get an idea of what the gauge is really reading.

 

[Timber]

I can't fault you for testing, my motto is "Trust, but verify." But what I described is how these fuel gauges work, even new off the lot. Yeah, I had one of those, too.

Admittedly, the other three were and are gassers (I still have one civvy K5) but I don't see where the sender or gauge could know the difference between diesel fuel and gas.

FWIW, my fuel gauge is pegged a little past F since I brought it home. Just to be safe I added some diesel fuel after running it around a little and barely managed to get 3 gal in - it was full. So I have some fuel gauge testing of my own to do. I need to drive it a few hundred miles and see if the needle does what it should. I may have a ground repair of my own to do.

But don't be spooked about it going past the F mark when it's full. That in itself doesn't mean anything. They do that even when they're working properly.

Good luck with it.

 

[wallew]

Both of my M1009's AND my M1028A2 go past the 'F' for full mark on the gauge.

They ALL go to 'E' for when it's empty. And once it hits 'E' I better find a fueling station or I will be walking soon.

So I don't see it being odd or abnormal. But hey, IT IS A CHEVY.

 

[mikes47jeep]

It sounds like typical 80's GM

There are 2 wires at the sending unit that deal with the fuel gauge; one grounds the sending unit to the frame or body, and the other goes to the gauge

You have to turn on the key to test this

If you unplug the gauge wire at the sending unit the gauge should read full or more than full

If you ground out the gauge wire the gauge should read empty

A weak ground, or a dirty gauge wire contact at the sending unit, will give you a false readings more so to the full side

A short in the gauge wire somewhere between the sending unit and the gauge would give a false reading more so to the empty side, and will usually go directly to empty and not move

Clean tight connections; usually solve the problem, but sometimes it's a faulty sending unit

 

[erniemigi]

welp did all the test and it came back as a bad fuel guage, i don't think i am going to worry about replacing it right now, it semi works, got other more important things that need 2 be replaced that i know r not working at all, thanks everybody for the help and where to start looking, i think my wife is getting upset with me since i spend more time on SS and my MV, this site is addicting