I just bought a 2000 Civic coupe EX (D16Y8). In the engine compartment on the firewall is a white plastic piece situated next to an amber-colored plastic tubing with a free end (see picture). I am not sure what the other end of the tubing connects to, but it might merge with the evaporator drain tube?

Please help.

 

Congrats on the new car. Does that hose go to the bottom of the EVAP canister? If so it is a vent that should just be open to the air at the other end.

 

please excuse me for not knowing what the plastic housing parts under the dash are actually called.

if you look under the dash and to the left of the blower motor, there is a black plastic housing thing (the housing that the blower motor is blowing into) and at the back of that housing is a little outlet with a hose attached to it. i think that goes to the hose on the other side of the firewall that you are talking about.

now that i read mk378's post i think it is the evaporator canister/housing or whatever. i just took mine apart to vacuum out all the leaves that were trapped in it. i remember seeing the evaporator and expansion valve inside of it.

i had turned on my a/c before and got shot right in the eye with a piece of a leaf. cleaned it to prevent that from happening again.

i think that hose is how water gets out of the system... like you stop the car and turn it off, and then there's a puddle under the car from the a/c. i think that's what that's from.

 

mk and trust, thanks for the replies. I think mk's idea is close.

In my photo, the white plastic piece and amber tubing appear to be part numbers 16 and 64, respectively, (combined = part 30) in the illustration below from the Majestic Honda site.

Part 16 = drain joint
Part 64 = vinyl bulk hose
Combined part 30 = drain tube (sub)

It appears that the drain joint in my picture is broken. I have no idea what the purpose of the drain joint/drain tube is. The tube merges with a tube downstream of the canister filter (part 18). Any ideas on the function of the drain joint and drain tube?

 

I think it is for the fuel vapor canister (emissions) #14. Here it is on my 2000 Civic EX

you can see the top of the tube

and the bottom appears to be connected to the fuel vapor canister via 31 & 28 in the parts exploded view

 

TheJGB3, thanks for the pictures! Your first picture is really helpful because it proves that my drain joint is broken, though I'm still fuzzy on what the purpose of a drain joint might be. Does it permit the release of rising vapor released by the canister filter? I think that's what mk was suggesting.

 

It looks like it just holds the end of the tube up to let air in or out, but won't let water get in like having the tube point straight up could. The older models just had a simple tube that went straight down and was left open. Maybe this is some sort of trap arrangement so if liquid gasoline gets into the canister because of some abnormal condition, it won't run out under the car as easily.

There should normally be no gasoline or vapor at that tube. While the car is parked, the canister adsorbs any vapors from the tank in it's charcoal filler. Only air should leave the tube. When the car is running, the canister is connected (thru a restriction) to the intake manifold and air is drawn in the bottom tube slowly, which releases the vapors trapped in the charcoal to be burned in the engine.

Unburned gasoline evaporating into the air is a major pollutant. It will react with sunlight to become "photochemical smog". Thus these canister systems were some of the earliest antipollution devices to be required on cars.

 

mk, thanks for the education, as usual. I'll order from Majestic the little white plastic holder to prevent anything from falling into the end the exposed drain tube.

 

mk, by the way, this forum could really benefit by someone like you with extensive Civic knowledge writing some DIYs. I understand that this would take a lot of time though.