OBD Guide

P1304

Cylinder 4 Misfiring Detected

Severity
⚠️ Medium
Can you drive?
Do not drive — repair immediately
Approx. repair cost
$6–56 (est.)

Symptoms

  • The engine runs rough or shakes
  • Power Loss
  • Increased fuel consumption
  • Check Engine Light Is On
  • Popping sounds in the exhaust system

Causes

  • Faulty spark plugs
  • Problems with the ignition coil
  • Clogged fuel injectors
  • Low cylinder compression
  • Problems with sensors (mass air flow sensor, crankshaft position sensor)

How to Fix

  1. Check the condition of the spark plugs in cylinder 4
  2. Check ignition coil and wires
  3. Clean or replace fuel injector
  4. Check compression in cylinder
  5. Check the operation of engine sensors

Related codes

Error P1304 by Vehicle Brand