P21FF
Fuel Control System B Too Rich at Higher Load Bank 2
P21FF is an OBD-II diagnostic trouble code meaning: Fuel Control System B Too Rich at Higher Load Bank 2. Common causes: oxygen sensor malfunction (bank 2), problems with fuel injectors (seizing, leaks). Estimated repair cost: $17–89.
Symptoms
- Increased fuel consumption
- Reduced engine power
- Black smoke from the exhaust pipe
- Unstable engine operation at high speeds
- Gasoline smell from exhaust
Causes
- Oxygen sensor malfunction (bank 2)
- Problems with fuel injectors (seizing, leaks)
- Malfunction of the mass air flow sensor (MAF)
- Increased pressure in the fuel system
- Air filter dirty or damaged
How to Fix
- Check and, if necessary, replace the oxygen sensor of bank 2
- Diagnose and clean or replace fuel injectors
- Check the operation of the mass air flow sensor and replace if necessary
- Check fuel system pressure and pressure regulator
- Replace the air filter
Related codes
Error P21FF by Vehicle Brand
FAQ
What does the P21FF code mean?
P21FF is an OBD-II diagnostic trouble code that indicates: Fuel Control System B Too Rich at Higher Load Bank 2
What causes a P21FF error code?
The most common causes of P21FF include: Oxygen sensor malfunction (bank 2); Problems with fuel injectors (seizing, leaks); Malfunction of the mass air flow sensor (MAF); Increased pressure in the fuel system.
How do I fix a P21FF diagnostic trouble code?
To fix P21FF: Check and, if necessary, replace the oxygen sensor of bank 2. Diagnose and clean or replace fuel injectors. Check the operation of the mass air flow sensor and replace if necessary. For a complete diagnosis, use an OBD-II scanner.
Is it safe to drive with P21FF?
Yes, but get it checked soon
How much does it cost to fix P21FF?
The estimated repair cost for P21FF is $17–89. Actual cost depends on your vehicle, location, and labor rates.
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