P0671 Code: Cylinder 1 Glow Plug Cylinder / Open

Does your vehicle have starting issues or a check engine light? Plug a scan tool into your vehicle to check if your vehicle’s powertrain control module (PCM) has any stored trouble codes. If the P0671 code has been triggered, read this article to learn about the code’s definition, common causes, and common symptoms.

What Does the P0671 Code Mean?

The P0671 code is defined as Cylinder 1 Glow Plug Cylinder/Open. The P0671 is stored when the PCM detects a malfunctioning glow plug located in cylinder #1. Some diesel engines have glow plugs. Each cylinder in the engine is typically fitted with a glow plug, which is a pencil-sized rod that is inserted into the engine that heats up very quickly during engine start.

When the key is turned, the glow plug control module or PCM will power the glow plugs for a set amount of time, which activates them and heats the nearby combustion chamber (or pre-chamber). Since diesel needs high temperatures in order to combust properly and efficiently, a faulty glow plug typically results in problems in starting the vehicle’s engine.

Note: The definition of the P0671 code can be different depending on the vehicle manufacturer. Consult the appropriate repair manual or repair database for the exact code definition.

What are the Common Causes of the P0671 Code?

The following problems can cause the P0671 code to be stored:

• Failed glow plug control module
• Failed glow plug wiring harness
• PCM failure
• Failed glow plug

What are the Common Symptoms of the P0671 Code?

The P0671 code can cause your vehicle to show the following symptoms:

• Difficulty starting or refusal to start in cold weather
• Engine knock while the engine is cold
• White smoke from the exhaust after the engine start
• Illuminated check engine light

How to Diagnose the P0671 Code

A faulty glow plug or glow plug control module might be the most common causes of this code, but a proper diagnosis is still essential before doing any repairs. However, a proper diagnosis can be difficult for those without any DIY experience because the part might not be easily accessible. The task might also require special tools or knowledge in order to test the concerned parts.

You should leave the task to a professional mechanic if you don’t think you’re up to the task.

Want to diagnose the problem yourself? Watch the video below to get an idea of what the process might involve:

How to Fix the P0671 Code

When it comes to resolving the problems causing the P0671 error code, your repair process should be based on your diagnosis. There is no universal solution for any DTC because repair procedures vary greatly between vehicle brands and models.

You should only begin repairs when you’ve identified the root cause. After you’ve identified the culprit, consult trusted internet repair resources and how-to guides. Consulting your repair manual or internet repair databases can also be beneficial because they might have important information regarding your issue.

Attempting to repair the P0671 error code can be tough, especially if you lack the necessary tools and experience. If you don’t have the necessary confidence to fix the issue yourself, don’t hesitate to consult a reputable mechanic.