charcoal canister

[gupta]

i was replacing my fuel filter and to get to it i had to take off the charcoal canister. but when i removed the charcoal canister only 2 of the 3 hoses were attached. the two hoses on top go to a temperature sensor and the fuel tank but i have no idea where the one on the bottom goes.

[kiasis]

You're fine. That's your #3 check valve allowing outside air into the canister to prevent the canister bladder from collapsing due to the vacuum created by the EVAP process. In other words, that hose on the bottom shouldn't be attached to anything, except perhaps some sort of retainer clamp to keep it from dropping off the car. It's there to pull in outside air.

Check out article #62: Emission#8 - Evaporative Emission Control.pdf on the website Automotive Training and Resource Site for more info. Our system is the non-ECU control EVAP system.

Especially if you don't have the BGB, I recommend downloading all the tech files from this website to your computer for easy access anytime you're stuck (I actually printed them all out as a second shop manual along w/ my BGB). The files are from a community college course (in California, community colleges are in between high school and university) for training future Toyota techs. The articles are easy to read and understand (literally, my first foray into auto repair on my 88GTS) and explain everything the BGB shop manual assumes you already know.