whats the other little canister attached to the fuel tank? I see the charcoal canister, but theres some other little can towards the rear of the tank attached to the side with a line going to the charcoal can.!!! Is that the Evaporative thing??? and can i take it off?? My evap codes are supposed to be turned off. Im building a fuel cell and going with a very small charcoal canister and dont want this other thing whatever it is.

 

That other little thing is the vent valve. It is a normally open valve meaning when it has no power it is open. Its only purpose is for the diagnostic test of the EVAP system. When all the planets align and the test runs the pcm closes the vent valve sealing the system, it opens the purge valve and puts engine vacuum to the closed loop fuel system and puts a certain amount of vacuum on it, closes the purge valve and then monitors how long it takes the pressure to leak off and then determines if there is an EVAP leak or not. If you have the codes disabled then no you don't need it. Like I said its only purpose in life is for when the PCM feels it needs to run the EVAP diagnostic test in which then the vent valve is told to shut to seal the system.

 

awesome!! Thank you so much man i couldnt find anything anywhere about it..lol

 

LOL, so true...with the parameters that have to be met it's a miracle that the EVAP monitor ever runs...

 

I drove a car 40 miles one day in the heat trying to get it to run the damn test to check the system out (per service managers request) and it never would run it. I decided it was ok and shipped it.