Good afternoon everyone, I recently purchased a 2000 SS with 25k miles. The fuel level always shows empty, and I have a code P0451 (Evap. Emission Control System Pressure Sensor Range/Performance).

Now, logic would simply say that because this car is an f-body, it wouldn't be crazy to assume the fuel level sender is bad and to just drop the tank and replace it. However, after looking at the attached wiring diagram, I am beginning to wonder if the P0451 code AND fuel level problem aren't related. I say this because it would appear that both sensors feed their data to the PCM via the same connector. Not to mention the low mileage, seems like something like this shouldn't go bad on such a "young" car.

That being said, does anyone know of a common failure point for this particular harness or wiring path? I am really hoping to avoid spending money on a new part and having to go through the process of dropping the tank for nothing. I also REALLY want to avoid creating the trap-door to access the fuel pump.

Thanks for the help!

 

Bump?

I really want to avoid (naturally) replacing the level sensor if I don't have to, because of the labor involved.

I read somewhere that the PCM won't conduct a tank pressure sensor check unless the tank level is between 15-85%, but with my level sensor not sending appropriate data to the PCM, the PCM then assumes my fuel level is always empty, thus not allowing it to run the pressure check. Is this correct? If so, my question still stands, if the PCM doesn't run the pressure check because it believes there's not fuel, why would I get a check engine light for pressure sensor low voltage?

Or, am I simply reading too far into this....and I need to drop my dang tank and see WTF is going on. I checked the wiring last weekend at the through-body bulkhead, but that was a very limited check and everything appears normal.

Thanks again!!