Gas cap venting issue
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Joined: Jun 2022
Posts: 63
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From: Imperial, MO
Gas cap venting issue
Replaced generic cap with OEM gas cap and still won't vent. When I unscrew the cap there is a rush of vapor escaping. Does anyone have a better solution for a replacement cap?
1998 C5 with just over 100k on the clock. Replaced fuel pump/level sensor with a Delphi unit12/2022.
Thanks,
Brad-in-STL
1998 C5 with just over 100k on the clock. Replaced fuel pump/level sensor with a Delphi unit12/2022.
Thanks,
Brad-in-STL
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Joined: Dec 2014
Posts: 682
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From: Cincinnati Ohio
The gas cap does not vent. Pressure in the fuel tank is controlled by the Evaporative Emission Control (EVAP) system. It captures fuel vapor to prevent venting to the atmosphere.
which prevents gas
which prevents gas
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Joined: Sep 2013
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From: Cape Coral, Florida
Replaced generic cap with OEM gas cap and still won't vent. When I unscrew the cap there is a rush of vapor escaping. Does anyone have a better solution for a replacement cap?
1998 C5 with just over 100k on the clock. Replaced fuel pump/level sensor with a Delphi unit12/2022.
Thanks,
Brad-in-STL
1998 C5 with just over 100k on the clock. Replaced fuel pump/level sensor with a Delphi unit12/2022.
Thanks,
Brad-in-STL
You may have a stuck closed EVAP vent valve or a clogged EVAP canister…if you don’t have a scan tool or if your mechanical abilities don’t go beyond changing your gas cap seek a professional to diagnose this.
Thread Starter
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Joined: Jun 2022
Posts: 63
Likes: 20
From: Imperial, MO
Thread Starter
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Joined: Jun 2022
Posts: 63
Likes: 20
From: Imperial, MO
