gabrielsousa

i would like to know :

-in what situation gases goes to the intake manifold
-in what situation gases goes to the throttle body

when is the purge solenoid valve closes or open ?

thanks

4drEF

Vapors only release into the intake after operating temp has been reached and while the engine is driving - not at idle.


Into a port on the intake manifold? Never.


The line on the top of the canister gathers fuel vapors from the fuel tank mounted 2-way valve.
Also on top of the canister, there is a flat disc which is a valve. The top line goes to the purge cut solenoid.
When the ECU triggers the solenoid, vapors are introduced to the engine through the bottom line on the disc/valve and into the throttle body port.
The hose coming out of the bottom of the canister runs back to the fuel tank carrying liquid fuel.

gabrielsousa

thanks a lot,


what happens if i remove the purge solenoid valve and connect directly to the intake ?

i have a JDM TB that does not have the canister spaout. if i dont connect the canister to TB, to where the canister will release the vapors ?

lostforawhile

the hose on the bottom isn't liquid, it's how air travels through the canister to purge the vapors from the charcoal matrix, liquid/vapor is separated at the tank

4drEF

You are probably right.
Some systems have that hose venting to atmosphere and others route that back to the tank.
Been a while so I really can't say for sure what that hose is on these cars.

lostforawhile

once the valve opens then vacuum is applied at the top,allowing air to start to flow through the canister,evaporating the fuel stored in the charcoal, and it's then pulled into the engine and burned

4drEF

A lot of people remove the canister and solenoid.
They cap the port on the throttle body and route the vapor line from the gas tank down the firewall.
Vapors just go out under the car.

If you want to be environmentally friendly and keep the system, maybe you can add a tee fitting to one of the other lines coming off the manifold?

lostforawhile

you don't want to leave your system open with this corn gas garbage, water vapor can get into your tank, and it takes a very small amount of water to cause phase separation of your gas, then you end up with a layer of water and ethanol on the bottom of the tank with fuel floating on top, it's not an issue if you drive every day and you are adding gas a lot, but if it's sits it doesn't take long

gabrielsousa

thanks a lot for the information,

i made a test , a drive with cold engine, i connected the canister to the intake with out the purge solenoid valve, and didnt notice any thing different

tech8

When fuel evaporates inside the gas tank, the excess fuel vapors are transferred to the charcoal canister. The way the EVAP purge valve suppose to operate is to open while driving, so the engine can suck/purge fuel vapors out of the charcoal canister and use that to be burned with the normal air-fuel mixture.

If you connect the line from the canister without the EVAP canister purge valve, the car may become flooded during refueling. During refueling without the purge valve, even more fuel vapors are allowed to enter the intake manifold and your car can become flooded. Pressing the accelerator pedal gets the car to start from the flooded situation. With the canister purge valve installed, the valve should normally be closed during refueling.

lostforawhile

OP post a picture of your canister, you said it doesn't have a purge control valve? remember if you vent it to air, thats also letting fuel evaporate out of your tank, gas prices may have gone down, but they will go back up, and that's venting money basically, forget the environmental stuff, thats gas evaporating you could be using in your car,

gabrielsousa

this is what i have now.

i have netuneRTP and on log now i know that the PCS is open util ECT-74c, after ECT-75c PCS is close

EDIT:
i dont know if the check box is open or close