94 k1500 4x4, strong gas smell underhood

I recently purchased a used 1994 K1500 4x4 with 105,000 on the clock. The truck seems to run very well for the age and mileage. It takes a bit of cranking to get it started when cold, about 4 seconds of cranking (I know its an older vehicle and I'm spoiled by my focus which starts as soon as I touch the key), but fires right up when warm. My issue/concern is the strong odor of gas when it first fires, and then for a few minutes after I shut it off. It seems like its coming from the vapor cannister behind the drivers side headlight. How big of an issue is this? What problems can this cause? Should it be changed ($140)?? Thanks for the help!!

Nobody has any thoughts at all?

I think that can happen if the tank is topped of when filling. If my memory serves me right the only option at that point is to replace the canister as it could eventually cause issues. However without confirmation that the fuel is not coming from a different issue you might just be throwing parts at it.

The smell is there whether I have a full tank or it's empty, and all points in between. I only really notice is bad when I first fire it up and right after I shut it off. I cant see any broken hoses leading in or out of it either. I found a generic cannister for $52 so I may try it and see.

The smell is there whether I have a full tank or it's empty, and all points in between. I only really notice is bad when I first fire it up and right after I shut it off. I cant see any broken hoses leading in or out of it either. I found a generic cannister for $52 so I may try it and see.

this vapor cannister has controlling valves to suck vapor out of cannister when engine is running..then when engine is off switch connection to fuel tank to absorb gas vapors..then when engine starts connects to cannister to remove those trapped vapors..

lets say the controlling vacuum valves have a torn diaphram ???

then it sucks fuel out of the fuel tank when engine is on and floods the cannister.. I would gather info on your vapor cannister and search the scrap yard for a cheap fix...

until you get to fixing this disconnect this from the engine and plug the vacuum lines..this will work until you do the fix..

I'll see if I can find one at my scrapyard first before i buy a new 1. Guess that would explain why I went through a half tank of fuel in 115 miles if that valve is sucking fuel out of the tank. Thanks for the explanations on that!!

I disconnected the cannister and have driven the truck a few times. So far I havent noticed any strong gas smell. I'm going shopping for a new cannister.