I just recently purchased a 2013 Ram 1500. I have the check engine light illuminated. I was told by the dealership that it was due to it having an aftermarket exhaust system on it. I took it to Auto Zone and had them test it. it came back with a code # P018C which is in reference to a fuel pressure sensor. Does anyone know if this would be true? Or is it something else?

 

Yep. P018C is indeed fuel pressure sensor B circuit low.

 

Would an aftermarket exhaust cause this code? I was told by the dealership that the code P018C just pops up and it is the exhaust that is the issue.

 

Can't see the correlation.