2002 Blazer Fuel Sensor

My fuel sensor is going back and forth between full to empty causing the low fuel light to come on even after filling the tank. Anyone else having this frustrating issue?

youll have to have a scan tool hooked up to it and see if the computer is reading the proper fuel level in the fuel tank. if your fuel level sensor in the tank is reading steady while the gauge is fluctuating then youll need to have the stepper motor in the instrument clusster replaced. if the fuel level sensor is irratic on the scan tool then youll need the fuel level sensor in the fuel tank replaced


You most likely need a fuel sending unit, which will come with the new fuel pump assembly


Yeah the sender for my Buick was $300 so I just lived with the low fuel notice.

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Chevrolet Blazer Gas Gauge Problems (repairpal.com)

As the others have said, likely the fuel level sensor in the tank has failed. You do not need to replace the entire pump assembly. When the level sensor in my 2006 Trailblazer failed I pulled the tank down, removed the pump, and replaced just the sensor unit because the pump was healthy and showed no signs of wear. But whether or not you want to replace the entire assembly is up to you and your shop.

The gauge has been OK, but the low fuel warning light stopped working on my 1999 Honda Civic years ago. Twice my wife ran out of fuel while alone on a long trip. I hope that is more than enough of a reminder to both of us…

I traced the problem back to the fuel pump area. I trust the Honda original fuel pump and don’t want to change it for this minor problem.

Huh . . .

This vehicle is well over 20 years old and dropping the tank on this one is not particularly easy, compared to some others

Were it my vehicle . . . If I’m dropping the tank, everything inside will be replaced by high-quality parts, so that I in all likelihood won’t be dropping the tank ever again


On my Corolla that light is turned on by the gauge itself. Turns on when needle goes below a certain position and trips a switch inside the gauge-unit. The switch action seems to be damped & filtered, to prevent the warning light from turning on and off going over bumps. On your Civic, the corresponding switch must be in the tank, part of the fuel gauge sending unit. I presume you’ve already verified the dash warning light bulb is working.

I couldn’t tell whether the low fuel lights work on my cars or not because the fuel level hardly ever gets below a half tank.

In my case, the fuel pump was pulling just under 8 amps and pump RPM was +/- 6000. Waveform on a labscope was a textbook picture of a brand new pump. I had no reason to believe that this pump that had 140,000 miles on it would not last another 140,000 miles. That, coupled with the fact that I rarely keep a car longer than 5 years and I don’t charge myself labor, means that I replaced a $60 sensor rather than a $300 pump assy.

Like I said, that’s a discussion for the customer and the shop.

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That’s a good policy, if only b/c it makes the fuel pump’s job easier so it will likely last longer.

I routinely let my gas level go down near empty, including lighting the low fuel level light, and never replaced a fuel pump. I had about 190,000 miles on a 1998 Buick Regal when I sold it after 14 years and 187,000 miles on a 2005 Honda Accord after 12 years. I think my wife also let the fuel run low before filling up on her 2003 Olds Silhouette until the van stopped registering fuel level, then she filled based on mileage. She guessed that there was about a quarter tank when she filled up during the last 2 years we owned it. It was 14 years old when we donated it.


These could help.

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