Moose

I'm New Here
Dec 13, 2015
5
5
Miississauga
VetteCoins
533
Car
2007
Province
ON
My fuel gauge keeps going up and down. For example I will fuel up it would be ok full and then I drive for a while goes down says need fuel and the back up after a while. Any ideas what it can be?
 
My car does that too. How quickly depends on how many times I push the right pedal more than 1/2 way in a day.

Joking aside.... When you say "drive for a while" I assume you mean a short while. So if you fill up again the tank is almost full?

You have 2 tanks I believe and maybe there is something wrong because of that. Crossover piping or something relating to the level sensor. Should be easy to check with a meter and a "google" service manual. If its a problem someone else has had it is on a forum. Hopefully someone here has the quick answer for you though.
 
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Could be right off base here but it seems to me that I read somewhere that the "float" gets gummed up with crap gasoline and causes all sorts of issues. Again, could be wrong but I think that is why some folks were using Techron in they fuel system. Don't think you can buy in Canada however.

Have to admit Derek's response is probably more accurate.

Good luck getting it sorted.
 
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My 2012 Tahoe does that as well. I need to replace the fuel pump + Fuel Sender altogether since it's all in one module.. Cost is $1300 for the repair + parts. In the beginning, the fuel gauge started to be not accurate. I filled the tank up and the fuel gauge read full and it moved 2 inches and then it never worked again. For a while, it's stuck on empty and sometimes it will let me know I am low on fuel. Sometimes I would hit a bump on the road and the fuel gauge would bump to full and then switch back to empty. I have an engine light on too as well..
 
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My fuel gauge keeps going up and down. For example I will fuel up it would be ok full and then I drive for a while goes down says need fuel and the back up after a while. Any ideas what it can be?
Hi. I know that some time ago Shell gas was coating / gumming up floats in gas tank and causing problems in GM vehicles. That was a few years back but if yours is a 2007 it may of gotten some of that gas back then and along with a bit of age may be showing effects. Try the dealer, they are aware of the past problem and I believe had a cleaner for the tank that they suggested. Never know might work, inexpensive and easy to try. Good luck.
 
My 2000 does (or did) that, once I hit 1/3 of a tank, the needle would drop off the face of the earth. With about 1/8 of a tank left, it would come back to let me know I'm about to run out of fuel. One explanation was a gummed up rheostat, where the sensor would hit a dead zone. I used a couple of bottles of Sea Foam over a couple of tanks and the problem has mostly been gone. Others state that the sulfur in the fuel corrodes the sending unit so it can't be restored, so maybe I am lucky with there being a bit of a film. In my old workplace we cleaned our circuit boards by soaking them in toluene, which is also an octane boost! We had 5 gallon pails of the stuff, but I moved to another job before I could test it out, however, I bet that would clean any film off the sensors. And, if you were to do this option, do some research first to make sure you're comfortable with it.
 
Hi. I know that some time ago Shell gas was coating / gumming up floats in gas tank and causing problems in GM vehicles. That was a few years back but if yours is a 2007 it may of gotten some of that gas back then and along with a bit of age may be showing effects. Try the dealer, they are aware of the past problem and I believe had a cleaner for the tank that they suggested. Never know might work, inexpensive and easy to try. Good luck.

I use nothing but Shell premium which is supposed to have no ethanol. I've heard of other brands causing problems but who knows. Zero problems with Shell gas so far, with over 80K km on the odometer, knock on wood and the car is a 2005. The electronics on these cars are my biggest worry and can be expensive to repair, as mentioned above.
 
I use nothing but Shell premium which is supposed to have no ethanol. I've heard of other brands causing problems but who knows. Zero problems with Shell gas so far, with over 80K km on the odometer, knock on wood and the car is a 2005. The electronics on these cars are my biggest worry and can be expensive to repair, as mentioned above.
Hi. I know that some time ago Shell gas was coating / gumming up floats in gas tank and causing problems in GM vehicles. That was a few years back but if yours is a 2007 it may of gotten some of that gas back then and along with a bit of age may be showing effects. Try the dealer, they are aware of the past problem and I believe had a cleaner for the tank that they suggested. Never know might work, inexpensive and easy to try. Good luck.
Thank you I will try it out.
 
My 2000 does (or did) that, once I hit 1/3 of a tank, the needle would drop off the face of the earth. With about 1/8 of a tank left, it would come back to let me know I'm about to run out of fuel. One explanation was a gummed up rheostat, where the sensor would hit a dead zone. I used a couple of bottles of Sea Foam over a couple of tanks and the problem has mostly been gone. Others state that the sulfur in the fuel corrodes the sending unit so it can't be restored, so maybe I am lucky with there being a bit of a film. In my old workplace we cleaned our circuit boards by soaking them in toluene, which is also an octane boost! We had 5 gallon pails of the stuff, but I moved to another job before I could test it out, however, I bet that would clean any film off the sensors. And, if you were to do this option, do some research first to make sure you're comfortable with it.
Thank you Riley I appreciate your reply I will try sea foam see what happens.
 
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