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RescueYou2

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Discussion starter · #1 ·
HEY EVERYONE, MY CHECK ENGINE LIGHT IS ON!!! AND IVE BEEN INGNORING IT LONG ENOUGH. I HAD A FRIEND RUN THE COMPUTER AND IT CAME BACK AS AN EVAP LEAK... NOT A HUGE PROBLEM HOWEVER IM HAVING A HELL OF A TIME GETTING TO THE EVAP CONTAINER HOSES, ANY IDEAS?
 
Discussion starter · #4 ·
EVAP SYSTEM 2

YA I DID ALL THAT IVE COME DOWN TO A HOSE THAT IS BEHIND MY ARB WHICH I TOOK OFF AND IT IS ALSO (TO FIND OUT) BURRIED BEHIND AND UNDER ALL KNIDS OF OTHER STUFF. ANYHOW I THINK ILL JUST TAKE THE EVAP CANISTER OFF AND GO NUTS FROM THERE... ILL REPORT BACK SOUNDS LIKE A COMMON ISSUE.
-RYAN
 
Discussion starter · #9 ·
EVAP 3

I Think I FOUND the ProblEm, thanks For all the advice, I disconnected the battery and droVe around for A wHile and the light has Not come bAck on so well see oddly enough the mechanic said posting in all caps is not a possibility?... weird? haha no thanks for the help
- Ryan
 
GoingOffRoading said:
You'll want to leave the evap canister connected... you'll need it to pass smog. Just make sure all of the connections are good and air-tight.
Umm.. depends on where you go, I just went to a national chain and I don't want to self-incriminate, but let's just say they were not very observant. They refused to smog the jeep at first because the tires would not fit on the dyno's rollers, but after I pointed out it is full-time AWD that was not an issue. Surprisingly the jeep smogged extremily low, well under 50% of the national average.

- Matt
 
Quick emissions lesson. The canister is part of the evaporative emission control system. That has nothing to do with the tailpipe emissions. And it has to work all the time, 24/7. Evaporative emissions are gas fumes. Sometimes called unburnt hydrocarbons but usually that refers to the tiny amount of fuel that manages to make it the whole way through and out the tailpipe.

Other parts of the evap control include the gas cap, gas tank, purge selenoid, and some hoses. Back when your typical mechanic knew how to rebuild a carbuerator, the mfgs were adding charcoal canisters. At first the carb vent was the only source hooked up. Then the tank was,then the cap was changed from vented to semi-sealed pressure relief. The canister stored the fumes instead of letting them pollute the atmosphere. They had to go somewhere, the canister can only hold so much. That's the purpose of the purge selenoid. When the engine can handle a slighty rich mixture, the computer wil activate the purge slelnoid which allows the fumes to be sucked through a vacuum line from the canister.

So as you can see, the canister should not affect the drivability. It will not affect the tailpipe emissions. I'm not aware of any "emissions" test that will ID a missing or malfunctioning canister. Many states have a visual check for emissions devices, but they can be of various shapes, sizes, and locations. There cannot be a mechanic that knows where they and what they look like on all the vehicles out there. Some emissions checks will be failed if the inspector can smell gas, so I heard.
 
Mine was the gas cap. They smoked it and we couldn't find any leaks, but I noticed a gas smell toward the rear and heard the air coming out of the tank. Sure enough, they tested it and it failed.

Disconnecting the battery only clears it for a few days, it'll probably come back. So go to someone who can do a smoke test for you.
 
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