Fix for persistent PCV CEL codes P0451, P0455,P0456,P0496, or P04F0 -- wire wear & corrosion issue

[MavXL]

So after a few weeks and $400 dollars of parts I finally found the reason why I get a reoccurring CEL with a combination of codes P0451, P0455, P0456, P0496, and P04F0. The worst part is I had to spend $0 to fix it. Through chasing this issue and ended up replacing the fuel vapor separator (purge valve) and the fuel tank pressure sensor which totaled about $400.

Today I was under the truck and decided to volt test the connector to the fuel tank pressure sensor because I was getting a persistent P0451 CEL and a constant static pressure reading on FORScan. I got some erratic voltage and then I noticed the sheath around the wires was worn down and a tiny hole formed in the signal wire and corroded the wire. Spliced it back up and we’re good to go! Not saying the purge valve and/or pressure sensor weren’t bad but before you go throwing your money around check out your wires!

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[MavXL]

Forgot to add, but in the pics you can see where the felt liner was rubbing against the wires. I snipped the wire before I took a pic but it rubbed a hole into the signal wire and corroded the wire.