Engine-Codes.com
Engine-Codes – Generic – P0674

P0674 Code - Cylinder 4 Glow Plug Circuit Fault

Quick Answer

The diagnostic trouble code P0674 indicates a fault in the glow plug circuit of cylinder 4 in a diesel engine. Common causes include Worn-out or damaged glow plug in cylinder 4, Faulty glow plug relay, Loose or corroded electrical connections. 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
P0674 indicates Cylinder 4 Glow Plug Circuit Fault.
Common causes
Common causes include Worn-out or damaged glow plug in cylinder 4, Faulty glow plug relay, Loose or corroded electrical connections.
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 12, 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 P0674 Description

The diagnostic trouble code P0674 indicates a fault in the glow plug circuit of cylinder 4 in a diesel engine. Glow plugs are essential components in diesel engines that help to ignite the air-fuel mixture in the combustion chamber, especially during cold starts. When the engine is cold, the glow plug heats up to increase the temperature of the combustion chamber, making it easier for the diesel fuel to ignite. A faulty glow plug in cylinder 4 can lead to issues with starting the engine, reduced fuel efficiency, rough idling, and increased emissions.

OBDII Code P0674 - Cylinder 4 Glow Plug Circuit Fault
P0674 Code - Cylinder 4 Glow Plug Circuit Fault

Common Causes of P0674

  1. Worn-out or damaged glow plug in cylinder 4
  2. Faulty glow plug relay
  3. Loose or corroded electrical connections
  4. Malfunctioning engine control module (ECM)
  5. Wiring issues in the glow plug circuit

Symptoms of P0674

  1. Difficulty starting the engine, especially in cold weather
  2. Rough idling or misfiring
  3. Reduced fuel efficiency
  4. Increased emissions
  5. Illumination of the check engine light

How to Fix P0674

  1. Diagnose the specific cause by using a diagnostic scanner to retrieve the fault codes and test the glow plug circuit in cylinder 4.
  2. Inspect the glow plug in cylinder 4 for damage or wear and replace it if necessary.
  3. Check the glow plug relay for proper functioning and replace it if faulty.
  4. Inspect and clean any loose or corroded electrical connections in the glow plug circuit.
  5. Test the engine control module (ECM) for proper operation and replace if necessary.

Cost to Fix P0674

The typical repair costs for addressing a cylinder 4 glow plug circuit fault can range from $100 to $300, including parts and labor. However, the specific diagnosis time and labor rates at auto repair shops can vary based on factors such as location, vehicle make and model, and engine type. It is advisable to contact local repair shops for a more accurate estimate based on the specific circumstances. Additionally, rates may be higher at dealerships or metropolitan areas and lower at independent shops.

What does this mean?

Tech Notes for P0674

























User Submitted Video

When is the Code Detected?

The Engine Control Module (ECM) has detected a fault in the cylinder #4 glow plug circuit

Need more information about the P0674 code?

Need more information on how to fix the P0674 code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P0674 code diagnosed by a professional: Find a repair shop in your area

Code P0674 Information for Specific Makes

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 P0674 Code

No Frequently Asked Questions about P0674 Code found.

Discuss the causes and fixes for P0674 OBDII Code

Submit a New Comment

Code P0674 comments

No comments found for this page.