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Changed fuel cap, engine threw a P0442 and P0456 today
Over the weekend, I changed out the gas cap and did some work under the hood, replacing my valve cover gaskets. I've been getting these codes intermittently so I bought a brand new gas cap but it didn't seem to have fix the issue.
I see talk about P0442 a lot but there's very little mention of P0456. Could they both be caused by the same issue? What's the best method to diagnose and narrow down this issue?
I tore into the engine today again and found two potential leak points. I fixed the near the service connection point (green plastic cap with a connection) but the other one near the CCV I didn't have the correct parts.
I've got a loose lose coming out of the CCV into the air box but I'm under the impression that the loose hose is on the other side of the evap pressure test system. Meaning, the CCV closes and the system is pressure sealed at the ccv isolating it from the air box, right? This shouldn't throw an engine code right?
11-19-15, 05:13 AM
Changed fuel cap, engine threw a P0442 and P0456 today
