My car has a P0451 code which is related to fuel pressure. I took it to get it looked at to see what it would cost and they said, I need a new catalytic converter. But they have a hard time finding that part, however I didn't think that code had anything to do with it. Is he trying to rip me off?

 

P0451 is the fuel tank pressure sensor acting up. not the fuel pump. It is a drop the tank unscrew the sensor repair. Could be frayed wires shorting.
Yes, if that is the only symptom run away. Unless AZ suddenly went al CAL on emissions I don't know why sourcing a cat would be a problem. They are available on ebay.

 

I would ask more questions about why they think it needs a cat. The P0451 is certainly no basis for that. It’s a problem with the fuel pressure sensor. Is that the only code? Are there any symptoms? What are they?

keep the original cat if it all possible. Replacing it unnecessarily is a big mistake.

 

it doesn't really have any symptoms.Besides the light, and that is the only code

 

Not that expensive and fairly easy to change

https://www.rockauto.com/en/catalog/...re+sensor,6385

You don’t have to completely drop the fuel tank