Reposting this from a tech thread I made in the OT section just to keep consistency with my ongoing maintenance/diagnostic stuff.
http://ecomodder.com/forum/showthrea...oid-32384.html
So after some reading, and quite obviously, this solenoid valve is a part of the evap/emissions system with the charcoal canister. Some have stated that without this valve the car could potentially run rich or develop a smell of fuel. Removing it will also negatively affect gas mileage.
Like I mentioned before, the previous owner removed the one on this car for whatever reason, as well as the other charcoal canister lines.
Before, nothing there but the screw, vacuum line hanging below, plug freely hanging (looks identical to IACV connector but different colored wires).
The valve, which for test purposes, I picked up at Pick-N-Pull for $5. I figured it would be worth the few dollars compared to the $130 price Honda wants for a new one. Also not even sure if it matters, but the top "dome" looking piece is a filter that clips into the valve, it's replaceable and costs $9 from Honda.
Installed with connector back in and correct vacuum hoses, the top nipple connects to the top port of the charcoal canister, the bottom nipple connects right below to the intake manifold.
Followed the diagram here for the vacuum lines:
I am a little disappointed that this did not get rid of my occasional idle issue where it will drop drastically low or sometimes stall. My idle is not sporadic, so I figure it is something small but I have determined there are no vacuum leaks. Will be replacing the map sensor here soon to see if that helps.
I will say though, that the car feels a little smoother at idle. Will it improve my fuel economy? We'll see come the next few tanks.