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Fuel Gauge trouble

I drive a 1989 Toyota Camry LE with a V6 Engine. When I fill my gas tank, start the car, the fuel gauge pointer doesn’t go completely into the “F” mark, see picture; I’ll even wait after driving a few miles if the pointer will try to go past the “F” mark, but it won’t. Could it be the gauge be faulty or the sending unit in the gas tank that’s causing the gauge to read inaccurately?

The picture shows after filling my gas tank completely

I would ask if for any reason the sender has been taken out of the tank? Did you get a new fuel pump or something that may have caused the inaccurate reading?

It is easy to bend the arm when you remove the sender from the tank thus causing an incorrect reading. Getting it back correct may be a whole new issue without just replacing the sender. Another cause to things like this is a couple broken ground straps. This would cause a shift in the resistance measurement the sensor can provide.

Last thought, was the car ever wrecked? I have seen the float potentiometer damaged from car accidents also.

Do you know when it started doing this?

Is the gauge causing a problem?

If the fuel gauge functions normally (as you drive more miles, the gauge moves toward empty), I don’t think you have a big problem. Your car is almost 14 years old and perhaps the float isn’t as bouyant as when the car was new.

The problem is more than likely the fuel gauge sending unit inside the gas tank. As they wear the electrical resistance of the sender increases and this artificially drives the dashboard gauge needle lower than normal.

The sender could be removed and physically checked by hand with an ohmmeter to verify this problem as long as the factory specs on resistance are known.

If it was right before, and now it’s not, it’s probably the sending unit.
The sender is a rheostat and a portion of it has stopped ‘‘sending’’ after all these years.

My biggest advice ;
is EMPTY accurate ?
as long as empty is accurate it doesn’t matter what it says for full.

I’ve had to adjust two vehicles over the years because empty was inaccurate ( you’d run dry when indicating some still there )
In doing so , bending the float arm for empty accuracy, the full became offset a bit.
It was oh so much nicer to have empty accurate that I insist you do nothing unless you have an issue with the indication of empty.

My 79 Chevy short stepside pickup I still own is one of those. The needle will stay on full and not budge for a hundred miles. But , man is it nice to know true empty.

Last thought, was the car ever wrecked? I have seen the float potentiometer damaged from car accidents also.

Do you know when it started doing this?

The car only had a front end wreck 21 years ago & no I didn’t drive it back then.

The fuel gauge problem started occuring mid-late last year when the weather got cooler