Can you remove 86 944 EVAP system

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Thom
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I did notice some fuel smell once or twice in the 18 years I have had the car but I cannot really remember how hot the weather was, though that cannot have been as hot as in the desert and I try to never leave the car parked under direct sunlight, if only to preserve the dashboard.
'90 944 turbo

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Jacquiles
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944er wrote: Thu Jul 25, 2024 8:28 pm The smell comes when the gas tank gets warm enough for the gas to evaporate and push fumes out. This becomes very apparent in the desert. If you keep the "two way valve" in the rear, the vapor pressure must exceed 2 psi for fumes to come out, which might not happen in colder climates. If you simply vent the tank to atmospheric, you will notice it at lower temperatures.
Ok interesting. As of right now i’m leaning towards just leaving it. I don’t think i have any issues with the evap system currently but don’t know for certain. Although i can smell gas from the front driver side near charcoal canister and in the car sometimes during heavy acceleration/throttle

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Tom
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If you are smelling gas with the charcoal canister still installed, I'd check the hoses for leaks (and the tank itself if you can get to it). It's sure not going to help the gas smell to remove the system and vent the tank to air, not to mention Greta Thunberg pounding on your door. I rebuilt the canister in my old Mercedes by cutting off the bottom, dumping out all the old charcoal, and replacing it with a couple pounds of activated charcoal (used in aquariums if memory serves), which all but eliminated the smell in that car. After 40 years or so, the charcoal was just dust and wasn't doing much.

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Bergerac
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I've deleted all of the vacuum controlled valves in the engine bay and replaced them with a solenoid valve off an Volkswagen that is normally closed. Mines controlled by my standalone, but I'm sure you could come up with a creative way to trigger it.

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dr bob
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I'm with Tom and Greta. The vapor system is benign as far as performance, but does a huge amount for emissions. Thinking that we live in the boonies and it won't really affect anyone isn't exactly correct.

Our previous home above L.A. had a fabulous ocean view, from Santa Monica Bay to Newport and out beyond Catalina Island. On many days, visibility was less than a mile and a backdrop the color of brake dust thanks to HC and sunlight mixing and the right wind direction. Much better than 25 years earlier, with less effort on capturing vapors, and maybe a quarter of the cars. But still. But it's just one car... The cannister and a couple valves aren't heavy.

Do your part. Please. :wave:
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Jacquiles
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Tom wrote: Fri Jul 26, 2024 12:06 pm If you are smelling gas with the charcoal canister still installed, I'd check the hoses for leaks (and the tank itself if you can get to it). It's sure not going to help the gas smell to remove the system and vent the tank to air, not to mention Greta Thunberg pounding on your door. I rebuilt the canister in my old Mercedes by cutting off the bottom, dumping out all the old charcoal, and replacing it with a couple pounds of activated charcoal (used in aquariums if memory serves), which all but eliminated the smell in that car. After 40 years or so, the charcoal was just dust and wasn't doing much.
Ok cool i’ll try replacing that canister. I have replaced the rubber lines for the evap system that is in the engine bay and that goes to the evap canister but those are the only ones. Thank you Tom

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