P04B4
Refueling Vapor Control Valve Stuck Closed
Same as P04B3 with the valve stuck closed - vapor cannot reach the canister during refueling, vapor escape from the filler is possible.
Same as P04B3 with the valve stuck closed - vapor cannot reach the canister during refueling, vapor escape from the filler is possible.
Common causes
- high
Valve stuck closed due to seal or debris
One of the most commonly reported causes for this code — check this first.
Typical part cost: $130-440
- low
Carbon or debris buildup preventing free movement
Less common, but worth ruling out after the more likely causes.
Typical part cost: $130-440
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First things to check
- 1Confirm the code with a scan tool and check for additional related codes.
- 2Inspect the relevant sensors, wiring, and connectors for damage or corrosion.
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Related codes
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Frequently asked questions
What does P04B4 mean?
P04B4 means "Refueling Vapor Control Valve Stuck Closed". It is a generic OBD-II code that points to a fault in the auxiliary emission controls.
What are the most common causes of P04B4?
valve stuck closed due to seal or debris; carbon or debris buildup preventing free movement; component wear with age - mechanical play — these are the most commonly reported causes. Verify with a proper diagnosis before replacing parts, or use the Wrenchify app for a vehicle-specific diagnosis.
Can I keep driving with this code?
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical. Use the Wrenchify app for a full diagnosis specific to your vehicle.
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