I have a 2007 Chevy Trailblazer, The gas gauge works when I put fuel in it and then when I start driving it falls to empty and the buzzer rings like I don't have gas and I've noticed that just idling the gauge will move back up to one half or full tank. As soon as I start driving it will fall back to empty. Is this electrical problem or my float in the tank or could it be a sensor of some kind. Please help me to find the problem?
There is a Campaign from GM about the problem you are having. I have a copy of the Campaign below.
I got a copy of it from the Alldata information website.
Campaign - Fuel Level Sensor Contact Wear
Bulletin No.: 10054D
Date: September 19, 2011
Subject: -10054D Special Coverage Adjustment - Fuel Level Sensor Contact Wear
2005-2007 Buick Rainier
2005-2006 Chevrolet SSR, TrailBlazer EXT
2005-2007 Chevrolet TrailBlazer
2005 GMC Envoy XUV
2005-2006 GMC Envoy XL
2005-2007 GMC Envoy
The following statement has been added to the service procedure, "Note: Before installing new fuel level sensor parts, ensure that the blue wires on the fuel sensor board are seated in the connector." Please discard all copies of bulletin 10054C, issued September 2011.
On some 2005 model year GMC Envoy XUV; 2005-2006 model year Chevrolet SSR, TrailBlazer EXT, GMC Envoy XL; 2005-2007 model year Buick Rainier, Chevrolet TrailBlazer, and GMC Envoy vehicles, the contacts on the fuel level sensor may wear prematurely. This wear could cause the fuel gauge to read empty after filling the tank and cause the malfunction indicator light (MIL) to illuminate. As the fuel level in the tank drops, the MIL may turn off and the gauge may display a reading; however, the reading may indicate a slightly higher level of fuel than what is in the tank. Eventually as the contacts continue to wear, the fuel gauge will stop working and the MIL will illuminate continuously.
Special Coverage Adjustment
This special coverage covers the condition described above for a period of 10 years or 120,000 miles (193,000 km), whichever occurs first, from the date the vehicle was originally placed in service, regardless of ownership.
Dealers are to install a new design fuel level sensor. GM will pay 50% of eligible repair expenses, (parts and labor) and the customer will be responsible for the remaining 50%. The amount paid shall be calculated with reference to dealers' already approved warranty parts and labor rates.
For vehicles covered by Vehicle Service Contracts:
If the repair order is dated prior to August 10, 2011, the claim is to be submitted to the service contract provider. The customer should be reimbursed for 50% of the paid deductible.
If the repair order is dated on or after August 10, 2011, the customer is responsible for 50% of their deductible. The balance of the claim will be shared equally between GM and the service contract provider. See the Warranty Transaction section for additional details
If you need to contact GM the phone number is 1800-222-1020 for Chevrolet.