Gas gauge fluctuation

[Big D's 4Runner]

I've been noticing that my gas fluctuates going up hill and down hill about a quarter of a tank when its about half full. Finally filled it up today and the gauge fluctuates down to about half way or more. Thinking maybe a bad sending unit or possible gauge but it reads dead on it just floats way too much. Thanks for the help and advice in advance.

 

[nissanh]

After resetting my ecu, my fuel gauge also went crazy. Fortunately I didn't had time to replace it...... After about a month....... it works perfectly...

How many miles in your truck? I would suggest, just ignore the gauge... keep the tank full and use it and see what happens.

 

[Big D's 4Runner]

Its got a 182k on it. It reads accurate and the fuel light comes on like its suppose to but its so annoying watching it fluctuate.

 

[Drcoffee]

What gas are you using? When I used speedway gas last summer, the gas gas started reading inaccurate. Bad gas can damage the sender. Run some mid grade gas from a tier 1 gas station and see if it functions better after a couple of tanks.

 

[cordrayj1]

Dude speedway will make your truck run like ****. Does for me every time. Hence why I refuse to use their gas

 

[nissanh]

Even though it is slightly expensive, I use Shell or Chevron only..... It keeps my injectors/intake clean as their fuel already contains cleaning substances as well.

 

[LittleCaesar]

BP makes my 4runner run something awful. You have to think that with the lawsuit settlements that will be going on for years, they have to skimp/cut back in some areas.

Sunoco, Chevron, and Shell are tops for me.

I think a fellow member here replaced just his sender for $160 or so and it has worked well for him so far.

 

[Drcoffee]

I used the Speedway gas because we were given a gift card from a school function. From now on I will re-gift a tier 2 gas card.

Considering the sender I have in my tank is the newer version and it still made it malfunction, that must be some real crap gas.

 

[Big D's 4Runner]

I normally always run shell or Exxon in it so i don't think that could be the problem. Now that I've drove it some and its about a half a tank it doesn't fluctuate hardly any but Im sure it will once it gets lower. Looks like ill do a sending unit and a pump when i get some down time.

 

[Allen130]

I've been noticing that my gas fluctuates going up hill and down hill about a quarter of a tank when its about half full. Finally filled it up today and the gauge fluctuates down to about half way or more. Thinking maybe a bad sending unit or possible gauge but it reads dead on it just floats way too much. Thanks for the help and advice in advance.

I'm noticing the same thing in my 97 with 174k miles. When I go up a hill, the gas quantity goes up; down a hill, it goes down. Normally don't see much of a flux unless I'm on the hill for 1-2 mins. Then when I get back to level ground, it'll take some time for the needle to move back to a normal reading.

I've read several threads on many 3rd gens having this small but annoying issue... Is the consensus that a 16-year old fuel sender is the culprit?

As an aside, I'm not worried about running out of gas... I've been doing manual mpg math for every tank for about the last 10 years. Just asking if there exists an easy fix (fuel additive/cleaner/etc) that might help out. Thanks.