OBD Guide

P21A6

Cylinder 11 Air-Fuel Ratio Imbalance

P21A6 is an OBD-II diagnostic trouble code meaning: Cylinder 11 Air-Fuel Ratio Imbalance. Common causes: dirty or faulty fuel injectors, air leaks in the intake manifold. Estimated repair cost: $17–89.

Severity
⚠️ Medium
Can you drive?
Yes, but get it checked soon
Approx. repair cost
$17–89 (est.)

Symptoms

  • Uneven engine operation
  • Increased fuel consumption
  • Reduced engine power
  • Check Engine light comes on
  • Possible misfires

Causes

  • Dirty or faulty fuel injectors
  • Air leaks in the intake manifold
  • Oxygen sensor malfunction
  • Problems with the exhaust gas recirculation (EGR) system
  • Malfunction of the mass air flow sensor (MAF)

How to Fix

  1. Check the condition of the fuel injectors of cylinder 11
  2. Examine the intake tract for air leaks
  3. Check the functionality of the oxygen sensor
  4. Diagnose the EGR system
  5. Check the MAF readings

Related codes

Error P21A6 by Vehicle Brand

FAQ

What does the P21A6 code mean?

P21A6 is an OBD-II diagnostic trouble code that indicates: Cylinder 11 Air-Fuel Ratio Imbalance

What causes a P21A6 error code?

The most common causes of P21A6 include: Dirty or faulty fuel injectors; Air leaks in the intake manifold; Oxygen sensor malfunction; Problems with the exhaust gas recirculation (EGR) system.

How do I fix a P21A6 diagnostic trouble code?

To fix P21A6: Check the condition of the fuel injectors of cylinder 11. Examine the intake tract for air leaks. Check the functionality of the oxygen sensor. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with P21A6?

Yes, but get it checked soon

How much does it cost to fix P21A6?

The estimated repair cost for P21A6 is $17–89. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat