AutoCodes – Generic – P1304

P1304 Code - Cylinder 4 Misfiring Detected

Quick Answer

P1304 indicates Cylinder 4 Misfiring Detected. Common causes include Faulty Spark Plug #4, Faulty Ignition Coil 4, Ignition Coil 4 harness is open or shorted. Severity is Moderate - service should be scheduled soon. The vehicle may still be drivable for short trips if it runs normally, but avoid hard driving and repair it soon.

What it means: P1304 indicates Cylinder 4 Misfiring Detected.
Common causes: Common causes include Faulty Spark Plug #4, Faulty Ignition Coil 4, Ignition Coil 4 harness is open or shorted.
Severity: Moderate - service should be scheduled soon.
Can I drive?: The vehicle may still be drivable for short trips if it runs normally, but avoid hard driving and repair it soon.

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Code Popularity 27,510

How popular is this code, among other codes? Low

Repair Importance Level

Moderate (Service soon) (2 / 3)

Repair Difficulty Level

Advanced (Pro) (3 / 3)

What is this?

Table of contents Created and updated by William Orellana on Sep 13, 2019

Description
Possible Causes
How To Fix
Cost to Diagnose
Comments
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Code P1304 Description

OBDII Code P1304 - Cylinder 4 Misfiring Detected - AutoCodes.com — P1304 Code - Cylinder 4 Misfiring Detected

What does this mean?

What are the Possible Causes of the DTC P1304?

Faulty Spark Plug #4
Faulty Ignition Coil 4
Ignition Coil 4 harness is open or shorted
Ignition Coil 4 circuit poor electrical connection

How to Fix the DTC P1304?

Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P1304 code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.

Need more information about the P1304 code?

Need more information on how to fix the P1304 code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P1304 code diagnosed by a professional: Find a repair shop in your area

Information for Specific Makes

P1304 Acura — Cylinder Number 4 Random Misfire Detected
P1304 BMW — Misfiring Cylinder 4
P1304 Ford — EGR Calibration High
P1304 Honda — Cylinder Number 4 Random Misfire Detected
P1304 Hyundai — Phase Sensor
P1304 MINI — Misfiring Cylinder 4
P1304 Saab — Cylinder 4 Misfiring Detected

About the author: William Orellana is a Master Mechanic and Mechanical Engineer with over 30 years of experience diagnosing and repairing vehicles. Learn more about his background.