OBD Guide

P231C

Cylinder 9 Air-Fuel Ratio Imbalance - Adjustment At Limit During Balance

P231C is an OBD-II diagnostic trouble code meaning: Cylinder 9 Air-Fuel Ratio Imbalance - Adjustment At Limit During Balance. Common causes: malfunction of the fuel injector of cylinder 9, problems with the ignition system in cylinder 9. 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
  • Power Loss
  • Check Engine Light Is On
  • Possible misfire in cylinder 9

Causes

  • Malfunction of the fuel injector of cylinder 9
  • Problems with the ignition system in cylinder 9
  • Vacuum leak in the area of cylinder 9
  • Low compression in cylinder 9
  • Problems with the oxygen sensor

How to Fix

  1. Check the condition of the fuel injector of cylinder 9
  2. Check the ignition system (spark plugs, coils) of cylinder 9
  3. Check the tightness of the intake tract
  4. Measure compression in cylinder 9
  5. Check the operation of oxygen sensors

Related codes

Error P231C by Vehicle Brand

FAQ

What does the P231C code mean?

P231C is an OBD-II diagnostic trouble code that indicates: Cylinder 9 Air-Fuel Ratio Imbalance - Adjustment At Limit During Balance

What causes a P231C error code?

The most common causes of P231C include: Malfunction of the fuel injector of cylinder 9; Problems with the ignition system in cylinder 9; Vacuum leak in the area of cylinder 9; Low compression in cylinder 9.

How do I fix a P231C diagnostic trouble code?

To fix P231C: Check the condition of the fuel injector of cylinder 9. Check the ignition system (spark plugs, coils) of cylinder 9. Check the tightness of the intake tract. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with P231C?

Yes, but get it checked soon

How much does it cost to fix P231C?

The estimated repair cost for P231C is $17–89. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat