OBD Guide

P0312

Cylinder 12 Misfire Detected

P0312 is an OBD-II diagnostic trouble code meaning: Cylinder 12 Misfire Detected. Common causes: spark plug fault, problems with the ignition coil. Estimated repair cost: $56–167.

Severity
⚠️ Medium
Can you drive?
Limited driving only, diagnose soon
Approx. repair cost
$56–167 (est.)

Symptoms

  • The engine hesitates or runs unevenly
  • Power Loss
  • Increased fuel consumption
  • Check Engine Light Is On
  • Engine vibration

Causes

  • Spark plug fault
  • Problems with the ignition coil
  • Dirty or faulty fuel injectors
  • Low cylinder compression
  • Problems with the fuel system (lean or rich mixture)
  • Crankshaft position (CKP) sensor malfunction
  • Damaged wiring harness or contacts

How to Fix

  1. Check the condition of the spark plug in cylinder 12
  2. Check the ignition coil and its connections
  3. Check the fuel injector for contamination or malfunction
  4. Measure the compression in the cylinder
  5. Check the fuel system for leaks or blockages
  6. Check the CKP sensor and its wiring harness
  7. Clear the error and test drive to confirm the problem is resolved

Related codes

Error P0312 by Vehicle Brand

FAQ

What does the P0312 code mean?

P0312 is an OBD-II diagnostic trouble code that indicates: Cylinder 12 Misfire Detected

What causes a P0312 error code?

The most common causes of P0312 include: Spark plug fault; Problems with the ignition coil; Dirty or faulty fuel injectors; Low cylinder compression.

How do I fix a P0312 diagnostic trouble code?

To fix P0312: Check the condition of the spark plug in cylinder 12. Check the ignition coil and its connections. Check the fuel injector for contamination or malfunction. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with P0312?

Limited driving only, diagnose soon

How much does it cost to fix P0312?

The estimated repair cost for P0312 is $56–167. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat