One thing after another: Fuel gage/Fuel sending unit

[trentc]

Just amazing how all these problems are hitting me all at the same time.

I went to put some fuel in the tank, which before hand was at the 'E' mark.

I never turned the engine off and put only about 8 gallons in.

I got back in, I took off after after putting fuel in. I went to look where the gauge is at. WOW! It's reading well above full and the needle kept moving clockwise to the right and back to the full mark.

After getting home I see it settled down to the full mark. Starting back up, it went to the right again. Turn off and it's settled at the 3 PM spot on the dial.

Could this be dial or the sending unit?

Thanks again.

[Robyn]

Very likely the sending unit has taken the big POOP.

The sending unit varies the voltage to the gauge via a variable resistor.

If the sender get a short in it or an open it will read wierd.

If the sender is in an open condition it will read extremely high.

Looks like its time to drop the tank and replace the sending unit.

Probably a good time to replace the sock too. (new senders usually come with a new one)

Best

Robyn

[trentc]

Just what I thought :mad: The needle is now stuck in the 3 O'clock position.

Any ideas on how to identify the fuel tank size so I can order the correct sending unit?

I am see two types to order. One for 25 gallon, and another for 31/40 gallon.

Thanks!

Trent

[Robyn]

Burbs "Usually" have a large tank

Check the RPO sticker in the glove box and see what the build was
You should be able to dig up the RPO codes online and then see what the truck was built with.

Just a note, I have never seen a Burb with a 25 gallon tank. The Blazers had 31's and the Burbs usually had 40's

Every diesel Burb I have owned would run for a month :D on a fill up

Best

Robyn

[trentc]

After thinking about it, it does seem like a silly question, but I have never put more than $20 (which equals to 5 gallons?) of fuel in it since I Have had it in the past four months.

Oh and yesterday the fuel gauge started acting normal again, that is until I again left the engine running and put more fuel in it.

It seems to be working its way back to working normal again. I guess this means I can maybe delay fixing this until the summer as long as I turn the vehicle off before putting in more fuel.

I will look for those spots for the RPO code, but I do not remember seeing one in the glove box.

Thanks

Trent

[DennisG01]

If you can't find it, give a dealer a call with your VIN. They should be able to tell you what size. Some may not be "willing" to help - in their eyes it's a pretty old machine. You might have better luck if yuo stopped by in person.

Once you know the size (and have figured out your avg. MPG) you could atleast guestimate how many miles you can drive before needing a fill-up. I did this for about 2 years on my Accord before I finally swapped the sending unit.

[GMC Hauler]

After thinking about it, it does seem like a silly question, but I have never put more than $20 (which equals to 5 gallons?) of fuel in it since I Have had it in the past four months.

Oh and yesterday the fuel gauge started acting normal again, that is until I again left the engine running and put more fuel in it.

It seems to be working its way back to working normal again. I guess this means I can maybe delay fixing this until the summer as long as I turn the vehicle off before putting in more fuel.

I will look for those spots for the RPO code, but I do not remember seeing one in the glove box.

Thanks

Trent
Mine acted up and would start going back to normal for a while. Then it just stopped working. I replaced it (got it from rockauto.com), and did the job in 2 hours. just run the tank low before you start the job.