Hello

I own a '03 G35 AT Sedan, and I am getting a SES with the code P0455.

I tried replacing the gas cap, the problem is still there. (Q1) Also I am only getting around 300-350KM out of a full tank, which I think is very low? I read on this forums that some people are getting 400-450+

So I did my research and I found out that the EVAP Vent Control is probably the issue (seems to be a common problem). (Q2) And my question is, which part# should I replace?

I found many old posts regarding the same issue, but none of them had a final clear solution. I believe the OEM part # that comes with any '03 G is 14935-AM60B, but there is a newer style with the part # 14935-JF00B. (Q2 Contd.) So should I be installing the new part instead?

(Q3) And finally, is this part something that I should replace myself? or is there a possibility that I might damage my car somehow?

 

If the gas cap didn't fix it. Then you need to take it to a shop. One that has a smoke machine for evap systems. It will fill up the evap system, and where they see smoke. That's what will have to be fixed.