P21FD
Fuel Control System B Too Rich at Higher Load
This code indicates fuel control system b too rich at higher load (bank 1). It relates to the throttle actuator / cruise control / fuel trim and may affect performance, emissions, or drivability depending on the exact failure.
Fuel Control System B Too Rich at Higher Load (Bank 1)
Common causes
- medium
Faulty sensor or actuator
The component monitored by this code may be worn, failed, or reading out of range.
Typical part cost: $100-400
- medium
Wiring or connector issue
Corroded, damaged, or loose connections can cause circuit or signal faults.
Typical part cost: $100-400
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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
See related trouble codes
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Frequently asked questions
What does P21FD mean?
P21FD means "Fuel Control System B Too Rich at Higher Load (Bank 1)". It is a generic OBD-II code that points to a fault in the throttle actuator / cruise control / fuel trim.
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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