Engine-Codes.com
Engine-Codes – Chevrolet – P0304 2018 Chevrolet Silverado

P0304 2018 Chevrolet Silverado Code - Cylinder 4 Misfire Detected

Quick Answer

The diagnostic trouble code P0304 for a 2018 Chevrolet Silverado indicates that a misfire has been detected in cylinder 4 of the engine. Common causes include Worn or fouled spark plugs, Faulty ignition coil in cylinder 4, Clogged or malfunctioning fuel injector. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

What it means
P0304 2018 Chevrolet Silverado indicates Cylinder 4 Misfire Detected.
Common causes
Common causes include Worn or fouled spark plugs, Faulty ignition coil in cylinder 4, Clogged or malfunctioning fuel injector.
Severity
High - diagnose this code as soon as possible.
Can I drive?
Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
What is this?
Table of contents Created and updated by William Orellana on Sep 14, 2024
💬 Need more help? Ask Auto Expert for instant answers — it's free!
AutoCodes App

Fix Your Car Smarter

Try the New AutoCodes App!

Get complete OBDII diagnostics, repair solutions, and cost estimates, plus AI chat support on demand.

AutoCodes App on Google Play

Code P0304 2018 Chevrolet Silverado Description

The diagnostic trouble code P0304 for a 2018 Chevrolet Silverado indicates that a misfire has been detected in cylinder 4 of the engine. A misfire occurs when the fuel-air mixture in the cylinder fails to ignite properly, resulting in a lack of power, rough idling, and potentially damaging the catalytic converter over time. This issue can lead to decreased fuel efficiency, increased emissions, and potential engine damage if left unresolved.

OBDII Code P0304 2018 Chevrolet Silverado - Cylinder 4 Misfire Detected
P0304 2018 Chevrolet Silverado Code - Cylinder 4 Misfire Detected

Common Causes of P0304 2018 Chevrolet Silverado

  1. Worn or fouled spark plugs.
  2. Faulty ignition coil in cylinder 4.
  3. Clogged or malfunctioning fuel injector.
  4. Vacuum leaks in the intake manifold.
  5. Low compression in cylinder 4.

Symptoms of P0304 2018 Chevrolet Silverado

  1. Rough idling or vibrations while driving.
  2. Loss of power or acceleration.
  3. Engine misfires or hesitation during acceleration.
  4. Increased fuel consumption.
  5. Illumination of the check engine light.

How to Fix P0304 2018 Chevrolet Silverado

  1. Begin by diagnosing the specific cause of the misfire in cylinder 4 using a scan tool to identify the exact issue.
  2. Inspect and replace the spark plugs in cylinder 4 if they are worn or fouled.
  3. Test the ignition coil in cylinder 4 for proper functioning and replace if necessary.
  4. Check the fuel injector in cylinder 4 for clogs or malfunctions and clean or replace as needed.
  5. Inspect the intake manifold for vacuum leaks and repair any leaks found.

Cost to Fix P0304 2018 Chevrolet Silverado

The cost of repairing a cylinder 4 misfire in a 2018 Chevrolet Silverado can vary depending on the specific cause of the issue. On average, the cost of replacing spark plugs, ignition coils, or fuel injectors can range from $100 to $300 per part, not including labor costs. The total repair cost, including parts and labor, can range from $200 to $800 or more. It's important to note that labor rates at auto repair shops can vary, so it's advisable to check with local shops for a more accurate estimate.

What does this mean?

Tech Notes for P0304 2018 Chevrolet Silverado

The P0304 code means that cylinder 4 is misfiring or is randomly misfiring. Start by checking for intake leaks and if no leaks are found the next step is to replace the spark plugs on cylinder 4. If the problem persists more tests need to be done to diagnose the problem, see "Possible Causes".



There is a Factory Service Bulletins for All 2000-2020 Chevrolet Models:

2000-2020 Chevrolet Factory Service Bulletin OBDII Code P0304

This Factory Service Bulletin explains how this condition may be caused by significant carbon build-up on the intake and/or exhaust valves due to fuel contamination or incomplete burning of the fuel.

Need more information about the P0304 2018 Chevrolet Silverado code?

Need more information on how to fix the P0304 2018 Chevrolet Silverado code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P0304 2018 Chevrolet Silverado code diagnosed by a professional: Find a repair shop in your area

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.

Frequently Asked Questions about P0304 2018 Chevrolet Silverado Code

1. What does the OBDII code P0304 mean on a 2018 Chevrolet Silverado?

P0304 indicates a misfire has been detected in cylinder 4 of the engine.

2. What are the symptoms of a P0304 code in a 2018 Chevrolet Silverado?

Common symptoms include rough idling, reduced engine performance, hesitation during acceleration, poor fuel economy, and the check engine light turning on.

3. What causes a P0304 code in a 2018 Chevrolet Silverado?

Possible causes include a faulty spark plug, ignition coil, fuel injector, low compression in cylinder 4, vacuum leaks, or an issue with the engine control module (ECM).

4. Can I drive my 2018 Chevrolet Silverado with a P0304 code?

Driving with a P0304 code is not recommended, as it can cause further engine damage or damage to the catalytic converter if the misfire is severe.

5. How do I diagnose a P0304 code on a 2018 Chevrolet Silverado?

Start by inspecting the spark plug, ignition coil, and wiring for cylinder 4. Perform a compression test, check for vacuum leaks, and test the fuel injector for proper operation.

6. How do I fix the P0304 code on a 2018 Chevrolet Silverado?

Common fixes include replacing the cylinder 4 spark plug or ignition coil, cleaning or replacing the fuel injector, repairing vacuum leaks, or addressing low cylinder compression issues.

7. How much does it cost to repair the P0304 code on a 2018 Chevrolet Silverado?

Repair costs vary depending on the issue. Replacing a spark plug or ignition coil could cost $100–$300, while more extensive repairs like fixing low compression may cost significantly more.

8. Can bad fuel cause a P0304 code in a 2018 Chevrolet Silverado?

Yes, contaminated or low-quality fuel can cause misfires, including in cylinder 4, leading to a P0304 code.

9. Will a dirty air filter trigger a P0304 code on a 2018 Chevrolet Silverado?

A dirty air filter is unlikely to directly cause a P0304 code but can contribute to poor engine performance, which might lead to misfires over time.

10. How do I reset the P0304 code on my 2018 Chevrolet Silverado after repairs?

You can reset the code by using an OBDII scanner to clear the check engine light or by disconnecting the battery for 10–15 minutes. Ensure the issue is fixed before resetting the code.

Discuss the causes and fixes for P0304 2018 Chevrolet Silverado OBDII Code

Submit a New Comment

Code P0304 2018 Chevrolet Silverado comments

No comments found for this page.