Sounds like the fuel sending unit: Part of but separate from the fuel pump. I have attached what the sender does.
The bad, you still need to drop the tank to repair. You might as well replace the entire pump since the pump has 160,000 miles on it too. Just make sure it all comes as one unit to include the strainer. It just makes sense. Though a little more expensive, I would go with the OEM pump only because you don't' want to drop the tank any time soon after replacement though other pumps are still good.
Also, replace the fuel relay at the same time. Doesn't cost that much, good preventative maintenance.
The modular fuel sender assembly mounts in the top of the fuel tank and is spring loaded to the bottom. It is designed to:
Provide optimum fuel level in the internal fuel reservoir during all fuel tan levels and driving conditions.
Improve the measuring accuracy of fuel tank level.
Coarse filters contaminates from the fuel.
House fuel pump and helps prevent fuel pump noise.
Include a check valve to inhibit back flow of fuel from fuel system. The fuel sender consists of the following serviceable components: fuel pump, fuel sender, strainer, and level sensor.
Sunday, November 2nd, 2008 AT 10:47 AM