The dreaded check engine light illuminates your dashboard, and your trusty VW isn’t running quite right. A quick scan reveals the cryptic “P0670” error code. What does it mean, and what can you do about it? This comprehensive guide dives deep into the VW error code P0670, providing you with the knowledge and tools to diagnose and fix the issue, whether you’re a seasoned mechanic or a concerned car owner.

Decoding the Mystery: What is VW Error Code P0670?

The P0670 diagnostic trouble code specifically points to a malfunction within the glow plug control module circuit for cylinder number 10. Glow plugs are essential for starting diesel engines, especially in cold weather. They heat the combustion chamber, making it easier for the fuel to ignite. A problem with the glow plug control module or its circuitry can lead to starting difficulties, rough idling, and reduced fuel efficiency.

Why Does P0670 Occur? Common Causes and Culprits

Several factors can contribute to a P0670 error code. Identifying the root cause is crucial for effective repair. Here are some of the most frequent culprits:

• Faulty Glow Plug: A damaged or worn-out glow plug is the most common cause. Over time, the heating element can degrade, leading to inefficient operation or complete failure.
• Wiring Issues: Damaged, corroded, or loose wiring within the glow plug circuit can disrupt the electrical signal, triggering the P0670 code.
• Glow Plug Control Module Malfunction: The control module itself can fail, leading to erratic behavior and incorrect signals to the glow plugs.
• Blown Fuse: A blown fuse in the glow plug circuit can interrupt power supply, causing the P0670 code.
• Relay Problems: A faulty relay can also disrupt the power supply to the glow plugs.

Diagnosing the P0670 Error Code: A Step-by-Step Guide

1. Retrieve the Code: Use an OBD-II scanner to confirm the P0670 code. This is the first step in any diagnostic process.
2. Visual Inspection: Inspect the wiring and connectors in the glow plug circuit for any visible damage, corrosion, or loose connections.
3. Test the Glow Plug: Use a multimeter to check the resistance of the glow plug for cylinder 10. Compare the reading with the manufacturer’s specifications.
4. Check the Fuse and Relay: Inspect the fuse and relay associated with the glow plug circuit. Replace any blown fuses or faulty relays.
5. Test the Glow Plug Control Module: If all other components check out, the control module itself may be faulty and require replacement.

Resolving the P0670 Issue: Fixing the Problem

Once you’ve identified the cause of the P0670 code, the next step is to implement the appropriate fix. This may involve:

• Replacing the Glow Plug: If the glow plug is faulty, replace it with a new one.
• Repairing Wiring: Repair or replace any damaged or corroded wiring in the glow plug circuit. Secure any loose connections.
• Replacing the Glow Plug Control Module: If the control module is faulty, replace it with a new one.
• Replacing the Fuse or Relay: Replace any blown fuses or faulty relays in the glow plug circuit.

“Regular maintenance is key to preventing glow plug issues. Make sure your glow plugs are checked during routine service,” advises John Miller, a certified automotive technician with over 20 years of experience.

Preventing Future P0670 Errors: Proactive Maintenance Tips

Preventing the P0670 error code from recurring involves regular maintenance and proactive care:

• Regular Inspections: Inspect the glow plug wiring and connectors periodically for signs of damage or corrosion.
• Timely Replacements: Consider replacing your glow plugs as part of your regular maintenance schedule, especially if your vehicle experiences frequent cold starts.
• Quality Parts: Always use high-quality replacement parts to ensure reliable performance and longevity.

“Using the correct type of glow plug for your specific VW model is crucial. Using the wrong type can lead to performance issues and even damage the engine,” adds Susan Davis, a seasoned automotive engineer specializing in diesel engine technology.

Conclusion: Taking Control of Your VW’s Health

The VW error code P0670, while potentially troublesome, is manageable with the right knowledge and approach. By understanding the causes, diagnostic procedures, and solutions, you can effectively address the issue and keep your VW running smoothly. For further assistance or specialized tools, contact VCDSTool at +1 (641) 206-8880 and our email address: vcdstool@gmail.com or visit our office at 6719 W 70th Ave, Arvada, CO 80003, USA. We are here to help you navigate your automotive repair journey.

Using an OBD-II Scanner on a VW

FAQ: Your P0670 Questions Answered

1. Can I drive my VW with a P0670 code? While you can likely drive with this code, it’s best to address it promptly to avoid potential further damage or starting difficulties.
2. How much does it cost to fix a P0670 code? The cost varies depending on the root cause and whether you perform the repair yourself or hire a mechanic.
3. How long do glow plugs typically last? Glow plugs typically last between 60,000 and 100,000 miles.
4. What other codes are related to glow plugs? Other codes related to glow plugs include P0671, P0672, P0673, and so on, usually indicating an issue with a different cylinder’s glow plug circuit.
5. Where can I find quality replacement glow plugs for my VW? You can find quality replacement parts at your local auto parts store or online retailers.
6. Is it difficult to replace a glow plug myself? Replacing a glow plug is a moderately challenging task that requires some mechanical aptitude and the right tools.
7. Can I prevent the P0670 code from happening again? Regular maintenance and using high-quality fuel can help prevent future glow plug issues.