P21A2
Cylinder 7 Air-Fuel Ratio Imbalance
P21A2 is an OBD-II diagnostic trouble code meaning: Cylinder 7 Air-Fuel Ratio Imbalance. Common causes: dirty or faulty injector of cylinder 7, vacuum leak in the area of the 7th cylinder. Estimated repair cost: $17–89.
Symptoms
- Unstable engine operation at idle
- Reduced engine power
- Increased fuel consumption
- Check engine light comes on
- Possible misfire in cylinder 7
Causes
- Dirty or faulty injector of cylinder 7
- Vacuum leak in the area of the 7th cylinder
- Problems with the oxygen sensor or mass air flow sensor (MAF)
- Malfunction of the fuel pump or fuel pressure regulator
- Burnout of the exhaust valve in cylinder 7
How to Fix
- Check the condition of the injector of cylinder 7, clean or replace if necessary
- Inspect the intake tract for air leaks
- Check the readings of the oxygen sensors and mass air flow sensor
- Perform a compression test on cylinder 7
- Check the pressure in the fuel system
Related codes
Error P21A2 by Vehicle Brand
FAQ
What does the P21A2 code mean?
P21A2 is an OBD-II diagnostic trouble code that indicates: Cylinder 7 Air-Fuel Ratio Imbalance
What causes a P21A2 error code?
The most common causes of P21A2 include: Dirty or faulty injector of cylinder 7; Vacuum leak in the area of the 7th cylinder; Problems with the oxygen sensor or mass air flow sensor (MAF); Malfunction of the fuel pump or fuel pressure regulator.
How do I fix a P21A2 diagnostic trouble code?
To fix P21A2: Check the condition of the injector of cylinder 7, clean or replace if necessary. Inspect the intake tract for air leaks. Check the readings of the oxygen sensors and mass air flow sensor. For a complete diagnosis, use an OBD-II scanner.
Is it safe to drive with P21A2?
Limited driving only, diagnose soon
How much does it cost to fix P21A2?
The estimated repair cost for P21A2 is $17–89. Actual cost depends on your vehicle, location, and labor rates.
See also: Russian version · NationStat