OBD Guide

P0303

Cylinder 3 Misfire Detected

P0303 is an OBD-II diagnostic trouble code meaning: Cylinder 3 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

  • Engine troubles
  • Power Loss
  • Increased fuel consumption
  • Vibrations at idle
  • Check Engine Light Is On

Causes

  • Spark plug fault
  • Problems with the ignition coil
  • Dirty or faulty fuel injectors
  • Low cylinder compression
  • Problems with the ignition system
  • Vacuum leak
  • Malfunction of the mass air flow sensor (MAF)

How to Fix

  1. Check spark plugs and replace if necessary
  2. Check the ignition coil on cylinder 3
  3. Check fuel injectors
  4. Measure the compression in the cylinder
  5. Check the intake manifold for leaks
  6. Check the operation of the mass air flow sensor

Related codes

Error P0303 by Vehicle Brand

FAQ

What does the P0303 code mean?

P0303 is an OBD-II diagnostic trouble code that indicates: Cylinder 3 Misfire Detected

What causes a P0303 error code?

The most common causes of P0303 include: Spark plug fault; Problems with the ignition coil; Dirty or faulty fuel injectors; Low cylinder compression.

How do I fix a P0303 diagnostic trouble code?

To fix P0303: Check spark plugs and replace if necessary. Check the ignition coil on cylinder 3. Check fuel injectors. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with P0303?

Limited driving only, diagnose soon

How much does it cost to fix P0303?

The estimated repair cost for P0303 is $56–167. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat