8 replies to this topic

[ZBrink]

My 2000 Yukon XL with the 5.3L just got a new fuel pump 4 months ago. I currently have about 168k on the clock and the pump is new as of about 162k.

For the last several weeks my fuel gauge goes up and down, up and down and the low fuel light will even come on at times immediately after I fuel up or in the middle of an interstate trip.

Anyone know what might be causing this and how to correct it?

Thanks,
Zack

Edited by ZBrink, 26 February 2010 - 06:59 AM.

[VRSCA1]

Was the fuel tank level sensor replaced or the pump module only? Also the connector at the pump module could be an issue.But my money is on tyhe level sensor.Did them by the bushels when I was at the dealership bread/butter.

[ZBrink]

Was the fuel tank level sensor replaced or the pump module only? Also the connector at the pump module could be an issue.But my money is on tyhe level sensor.Did them by the bushels when I was at the dealership bread/butter.

Ooh...I have no idea. I order the part myself and took it to the shop. It was whatever was standard from what I understood at the time.

[ZBrink]

Several days ago and after the initial post for this thread I tried what was suggested in other posts similar to mine. I used the 24 gallon concentration of Chevron's Techron. I placed the entire amount into my empty tank and filled up with with about 15 gallons of 93 octane Chevron fuel.

Instantly my gauge began working correctly and it has been since that day. I'm keeping my fingers crossed that this solves my problem permanently!!

[Rampage1]

Several days ago and after the initial post for this thread I tried what was suggested in other posts similar to mine. I used the 24 gallon concentration of Chevron's Techron. I placed the entire amount into my empty tank and filled up with with about 15 gallons of 93 octane Chevron fuel.

Instantly my gauge began working correctly and it has been since that day. I'm keeping my fingers crossed that this solves my problem permanently!!

I am confused about this line " I used the 24 gallon concentration of Chevron's Techron". Do you mean regular pump gas or something else? My 2000 does the same thing as yours and it is a pretty common problem. I might try this on my truck.But i will give it a few days to see what happens with yours.My truck will sometimes work fine for a couple of days for no reason. Also if you swerve sharply left and right at slow speeds usually the gauge will work.

[Jimmyz]

My 2001 Suburban started doing this about a month ago.

I find it hard to believe that the grade & make of gas makes a differents.

But hey I'll try it.

[Jimmyz]

Here's an older post about this same topic...

Thanks for the replies. But the problem may not require major repair, or sensor replacement.

I got some good info from a radio show.

This guy (http://www.texascardoctor.com/) has a radio show on Saturdays where folks call in and ask questions. He has 50 years experience, and one of the most successful auto shops around for 25 years.

Anyway, I called in yesterday and he said that the problem was very common on GMC vehicles. It seems that some sulfur compounds build up on the contacts of the sensor and they will not make contact. The problem is exacerbated with the presence of methanol in the fuel. His recommendation was to go to an auto parts, buy two bottles of Techron, and double treat a tank of fuel. In most cases that solves the problem. The Techron bottle even states that it helps alleviate fuel gauge problems.

He also said that if one ever has to replace the fuel pump to only use an AC-Delco assembly, never an after market.

This post has been edited by spikefish: Jul 5 2009, 12:04 PM

[USMdude]

My 2000 Yukon XL with the 5.3L just got a new fuel pump 4 months ago. I currently have about 168k on the clock and the pump is new as of about 162k.

For the last several weeks my fuel gauge goes up and down, up and down and the low fuel light will even come on at times immediately after I fuel up or in the middle of an interstate trip.

Anyone know what might be causing this and how to correct it?

Thanks,
Zack

Does movement play in the gauge movements? Can you stop for a few minutes or when you first crank up and the gauge stay constant?

-Parked (with enough time for the fuel to quit sloshing)
-Sensor is bad or broken
-Wire problem
-Stepper motor

-Moving
-Short or ground.

That is just a couple.....

If it is moving all the time located the return voltage wire from the sensor and back probe and watch the voltage it should stay constant in voltage or ohms depending are transmitting the level back. It use to be voltage but the last one I had to hunt a sensor wire on was a 80tys model... So they could be using ohms now.

Jbo

[torranosaurus]

I I

My 2000 Yukon XL with the 5.3L just got a new fuel pump 4 months ago. I currently have about 168k on the clock and the pump is new as of about 162k.

For the last several weeks my fuel gauge goes up and down, up and down and the low fuel light will even come on at times immediately after I fuel up or in the middle of an interstate trip.

Anyone know what might be causing this and how to correct it?

Thanks,
Zack

Does movement play in the gauge movements? Can you stop for a few minutes or when you first crank up and the gauge stay constant?

-Parked (with enough time for the fuel to quit sloshing)
-Sensor is bad or broken
-Wire problem
-Stepper motor

-Moving
-Short or ground.

That is just a couple.....

If it is moving all the time located the return voltage wire from the sensor and back probe and watch the voltage it should stay constant in voltage or ohms depending are transmitting the level back. It use to be voltage but the last one I had to hunt a sensor wire on was a 80tys model... So they could be using ohms now.

Jbo