At Fixya.com, our trusted experts are meticulously vetted and possess extensive experience in their respective fields. Backed by a community of knowledgeable professionals, our platform ensures that the solutions provided are thoroughly researched and validated.
I have a 2005 GMC Envoy and recently every time I fill up the gas tank, it shows that it is full and then drops down to empty and then will keep bouncing around to half full, full, empty. This has happened the last two times that I have filled up. Any ideas/suggestions? It just started after my last oil change.
- If you need clarification, ask it in the comment box above.
- Better answers use proper spelling and grammar.
- Provide details, support with references or personal experience.
Tell us some more! Your answer needs to include more details to help people.You can't post answers that contain an email address.Please enter a valid email address.The email address entered is already associated to an account.Login to postPlease use English characters only.
Tip: The max point reward for answering a question is 15.
The new design filler neck on newer gm vehicles don't have a flap. The flap was just to keep stuff from falling in. I've had problems with the fuel sending unit in the tank on these vehicles.
The oxygen sensor has nothing to do with the fuel gauge. There are two possibilities for the gas gauge error, first it could be the in-tank gas level sensor or it could be a defective stepper motor which drives the gauge. A professional scan tool can determine the fuel level being sent by the in-tank sensor, if that disagrees with the gauge, then the stepper motor needs replacing.
You will need to remove the fuel tank from the truck and replace the fuel pump/fuel level sensor module that is inside the fuel tank. Use extreme caution when doing this as there is a real fire hazard.
Sending unit. Its all one unit including fuel pump, float, ect. The check engine light is because of the high or low resistance in the unit. Let me know if you have already fixed.. You have to drop the tank to get to it also.
×