Re: vent valve
The purge canister and solenoid are located underneath above the fuel tank. There is also a purge valve on the driver's side of the engine block.
"Brownstone Bumblebee" 2016 Diesel Colorado Z71 CCSB 4X4, Brownstone Metallic
2005 Z71 LS Crew Cab 4X4; gifted to my oldest child
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