i looked at my LS2 in the buick today, the port on the side of the intake is caped off, i must have removed the Evap solenoid assemble two years ago when we installed the motor and tranny in the car.

*also im not even sure if Sand & Street gave me the solenoid hook up in the custom wire harness they built for me last year, I think all that was deleated,

by the way what is erod manual ??

everyone thank you for your help

 

erod is the emissions legal engine package (engine, ecu, cats, charcoal can, etc) sold by GM.

 

I was under the impression that the fuel tank pressure sensor was one of the sensors used by the PCM to dictate when the purge would occur, but I guess maybe not? That's good to know since I'm putting the charcoal cannister in the truck I'm building now. I was just going to hook the vacuum up to a constant port like it was with the original carb. Guess now I'll hook it to the purge solenoid and have that turned back on in the tune. Thanks for the info Garys68.

 

My understanding is that the charcoal canister has 3 ports, tank, purge solenoid, and a vent. The ecu closes the vent and looks for pressure changes in the tank to confirm evap controls are working (source of the CEL with loose gas caps). The purge solenoid opens when the vent is open and the engine in closed loop. The vent allows the fumes to be pulled from the canister and closed loop allows for compensating for the vacuum leak. That way there's no excessive vacuum built in the tank.
I'm not sure of the conditions when the tank evap is checked or when the purge is opened.
If anyone can confirm or correct this?