Quote Originally Posted by HVACMAN View Post
I bought a canister from Amazon that would mount below the fuel tank, then plumbed the tank vent to the inlet. I ran a 1/4 inch line from the canister outlet to the purge valve on the engine. My LS came with the purge valve but no provision in the harness, so I brought an ignition accessory circuit to the engine and put a programmable micro timer in the circuit. 2009-11-23_172028_1.gifIMG_1049.JPGIMG_0090.JPGWhen the engine is started the purge valve is energized for 1.5 minutes.
Thats a great solution! I'm in the same boat. The engineer i'm using to certify the build wants to see that all emission controls on the motor are retained. While there was no provision in the harness for the purge valve, I contacted GMPP to see if the purge control logic was in the ECM hoping that I could just add wiring - answer was no.
My plan was to run wiring to the valve and plumb it to the canister, but leave the wiring unterminated inside the loom. At a glance, it would all look OK and pass inspection - who's going to check actual operation of the valve?

After reading the above about saturated carbon canisters, maybe I should rig up a 'HVACMAN' solution.