Inaccurate Fuel Gauge

The other day after driving 80 miles the fuel gauge read 1/2 tank. This is not a MPG PROBLEM! The mileage is still 15 mpg.
The last time after driving 30 miles the gauge went to 3/4 tank (5.5 gallons of gas in 30 miles NO WAY) Once the gauge hits 1/2 tank it stays there for over 100 miles.

The trailblazer is a LT 2004 with 5000 miles. Has anyone seen this before?

I just started noticing the fuel gauge being erratc
gary,2004 with 5500 miles

I had a similar problem with my Nissan Maxima. It costed $300.00 to fix a float in the gas tank. I have learnt an expensive lessen not to try and top up my gas tank to the rim. I stop pumping gas when the pump stops the first time. This is what the problem was with this car. It may not apply to yours, but it may be a possibility.

Read in a GM techlink that there is a reprogram for one of the computers in the vehicle that will correct this. Dealer should certainly be up on this and fix it.

I had this problem with my 2005 Trailblazer. The Dealer replaced the gas gauge last year under warranty - which involved pulling the gas tank - at about 55K.

Problem has resurfaced one year and 30K later. Dealer is now out of business and warranty has expired due to mileage.

Is there a warranty on parts and/or labor (Mopar did a one year warranty for the parts).

How often do gas gauges go out? Never had this problem before. Had a 65 Dodge van to 500K, 73 Gremlin to 150K (former hubby demo derbied it on the interstate), Prelude to 197K, Grand Cherokee to 188K.

Is it a computer problem as suggest by prior post? If so, why did Dealer replace gas gauge instead of fixing the computer problem?

Any ideas???

I have a 2005 trailblazer and i've had a similar problem. Mine started out doing what you are saying then it just stayed on E with the warning light on all the time. it was the fuel sending unit. The part was $120. They have to take the gas tank off to replace so it's about another $200 in labor. If you take it to the dealer they can check it. good luck. Mine has worked fine since getting it fixed

This thread is too old please check the dates before posting, thanks.