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Fuel gauge

I HAVE A 05 CHEVY TBLAZER. THE ONLY PROBLEM I HAVE EVER HAD IS WITH THE FUEL GAUGE. IT ALWAYS READS EMPTY. I KNOW THAT I COULD HAVE IT REPLACED, BUT THAT IS TOO COSTLY. SOMEONE TOLD ME TO USE CHEVRON FUEL ADDATIVE AND CHEVERON GAS. THEY SAY IN TIME IT WILL FREE UP WHATEVER IS CORRODED. ANY TRUTH TO THIS?

Please, turn off the ALL CAPS. It makes it hard to read. Those fuel additives may work, but I doubt it. I fear you have more than corrosion problems. To fix this, the tank will need to be dropped, and the sending unit inspected.

The sending unit in the gas tank is probably stuck or faulty. I doubt the gauge itself is the problem. The sending unit can be tested to see if it’s working. Fuel additives won’t make any difference.

This is rather annoying on a three-year-old vehicle. Did this happen before or after the warranty expired?

Agreed.

Excellent point about the age of the car and the warranty. The OP may also want to check to see if there are any TSBs on this problem.

I have a 01 chev. s-10 that had the same problem. I eventually had to replace the fuel pump (unrelated problem) upon inspection after I pulled the pump out, I noticed some wear on one of the pivot points on the guage float. This was causing it to hang up and read 1/4 all the time. I’m not sure if the 04 is the same as the my 01 or not. You can buy the 01 seperate and reploace it on the pump without buying the entire pump. Unless you do it yourself, it is very labor intensive.

I’ve had the same problem with my 2000 Blazer for about a year and a half now. Evidently high-sulfur gasoline leaves deposits on the sending unit in the tank.

Both Chevron Techron and GM Fuel cleaner state on the bottle that they can clean the sensor. As far as I can tell the GM Fuel Cleaner is rebadged Chevron Techron, execept it cost $28 a bottle instead of $8.

I tried both on my 2000 Blazer, it didn’t make a difference on the gauge but the truck ran a little smoother afterwards. Since your truck is newer, I would try a bottle of Chevron Techron, forget the GM stuff, too expensive.

I track my mileage between fillups. I try to leave a least 3 gallons in the tank before I buy gas. In the summer I can go safely between 260-270 miles and in the winter it’s about 240-250 miles before filling up.

Ed B.

I have heard from some that adding Techron to the tank got the sensor working again. If you try a couple of tanks of the cleaner and still have no results, then you may have to get it repaired.

My wife has a 2001 Pontiac Montana…The problem with her’s is that the gas gauge will read correctly above half a tank and then read full below half a tank before bouncing around from F to E… I only buy Chevron gas (habit/convience) and tried adding some Techron…The Techron made no difference to the gas gauage… Like others have said, we just track the mileage with the trip odometer instead of spending $600/so to get it fixed… We’ll just have it fixed when/if the fuel pump gives out. Good luck!