Hello, I'm Danny.
Here is the information you requested. It sounds like you are having an issue with the fuel sending unit. This unit built into the fuel pump assembly that is located inside the fuel tank. The fuel sender may be defective or failed and not giving a correct reading of the fuel level. You will have to change the fuel pump assembly to correct this issue. Here is a tutorial showing how to replace an in-tank fuel pump assembly:
You will have to remove the fuel tank to gain access to the fuel pump assembly. I've attached picture steps below on how to remove and replace both the fuel tank and fuel pump assembly on your Envoy. Hope this helps and thanks for using 2CarPros.
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Thursday, July 22nd, 2021 AT 12:19 AM