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Guest Message by DevFuse

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Gas tank pressurizing after charcoal cannister removal? (EA82T)

ea82 ea82t

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3 replies to this topic

#1 BoostedBoxer421


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  • Newport, WA

Posted 11 March 2016 - 03:31 PM

hey everyone,


I recently found a couple cracked vac lines on my charcoal cannister while sitting at work the other day, so I decided to just remove it since I don't have EGR or any other smog type stuff. after removing the cannister ive noticed my fuel tank pressurizes more than normal and i was wondering if there was a return line to the tank that i should put a check valve on or hook up somewhere else???


i have an 89 Loyale turbo thats moderately modified

-dual range swap (was 4eat)

-VF11 turbo


-MAF relocation

-Delta street cams (260*)

-3rd gen heads w/mild porting


Attached File  11027959_881126035327697_1231056822103892512_o.jpg   154.4K   6 downloads


thanks for any help!!

#2 nncoolg


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Posted 11 March 2016 - 06:41 PM

...you certainly wouldn't want to plug the tank vapor line :


#3 Fairtax4me



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  • Charlottesburg, VA

Posted 11 March 2016 - 06:42 PM

The canister has nothing to do with EGR. 

Its for the evaporative emission control system, which uses the charcoal to collect and store gasoline vapor from the fuel tank. 

Vapor in the tank is pushed out through a vent valve and to the canister as the tank pressurizes. The canister has a vent hose that runs to a filter, after vapor is run through the charcoal, the left over air is discharged through the filter.


You need to have a vent system in place or the tank will pressurize while you are driving and will force more fuel into the engine and cause running problems. 

It can also pressurize the tank in hot weather and cause liquid gas to be pushed out of the filler neck, or can cause the tank to rupture, especially in rusty places on the tank.


The easiest thing to do if you don't want to fix the canister is find the purge hose at the canister (it runs to the front of the car to the engine), and connect that to the vent hose from the tank. Disconnect the purge line from the purge solenoid on the engine. Find the vacuum supply hose for the purge solenoid and cap that off at the manifold. 

#4 BoostedBoxer421


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Posted 12 March 2016 - 12:59 AM

thanks guys! i knew it would be bad for mileage and probably cause other problems so i had to find out haha. ill set up a vent for the vapor line to the tank

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