Even if you’re not a mechanic, fixing the P0671 code on your diesel engine doesn’t have to be scary.
Use an OBD-II scanner to confirm the OBD2 problem, then check the glow plugs, wiring, and relay.
Common signs like hard starts, rough idling, and higher fuel use shouldn’t be ignored.
Use a multimeter to test the glow plugs and find the issue.
Want to boost your engine’s performance and avoid more problems?
Let’s look at the simple steps you can take to fix this error quickly.
Quick Navigation
Key Takeaways
- Use a code reader to find error codes and pinpoint what’s causing the P0671 code.
- Look over the glow plugs, wiring, and connectors to see if there’s any damage or rust.
- Check the glow plug resistance with a multimeter and replace any that don’t meet the required range.
- Check if the glow plug relay is working and swap it out if it’s not.
Understanding the P0671 Code
Understanding the P0671 code means knowing it’s a diagnostic trouble code for diesel engines. It shows there’s a problem with the glow plug control circuit.
Glow plugs help start diesel engines, especially in cold weather, by warming up the combustion chamber. If you see the P0671 code, it means this system isn’t working right, which can make starting the engine hard and reduce efficiency.
The issue might be with the glow plug relay, individual glow plugs, or the Powertrain Control Module (PCM).
Using the right tools to diagnose the problem is crucial for fixing it properly and quickly.
Importance of Prompt Attention
Addressing the P0671 code quickly is crucial to avoid more engine problems and expensive repairs. If you ignore this issue, you could face serious consequences like increased engine wear and potential failure. Not fixing this code can lead to lower engine efficiency, higher fuel consumption, and more frequent breakdowns. Taking care of it right away will save you money and help your engine last longer.
| Issue | Short Term Consequences | Long Term Effects |
|---|---|---|
| Engine Wear | More Wear and Tear | Possible Engine Failure |
| Fuel Consumption | Higher Fuel Usage | Lower Engine Efficiency |
| Engine Performance | Rough Idle, Misfires | More Breakdowns |
| Overall Costs | Immediate Repair Costs | Expensive Future Repairs |
Common Symptoms
When your vehicle has a P0671 code, you might notice some telltale signs that something’s wrong with the glow plug control circuit.
You could have trouble starting your car when it’s cold, meaning it takes longer for the engine to start. This is because the glow plugs aren’t working properly.
The engine might also run rough or misfire when you start it up, which is another clue that the glow plugs are having issues.
You’ll see the Check Engine Light come on, alerting you to a problem.
You might also see a drop in fuel efficiency because the engine isn’t burning fuel as well as it should.
Spotting these symptoms early can help you fix the problem and keep your car running smoothly.
Causes of P0671
The main reasons for a P0671 code are usually related to problems with the glow plug control module, bad glow plugs, damaged wiring, or electrical issues that affect the circuit. These problems can mess up the glow plug system, causing failures and malfunctions.
Here are the key causes:
- Bad Glow Plug Control Module: This module controls the glow plugs and can stop working because of internal issues.
- Faulty Glow Plugs: Glow plugs can wear out or break, making the system less efficient.
- Damaged Wiring: Physical damage or rust in the wiring can stop electricity from flowing properly.
- Electrical Problems: Issues like short circuits can mess up the glow plug circuit.
Knowing these causes is important for troubleshooting effectively.
Diagnostic Tools Needed
To figure out what’s causing the P0671 code, you’ll need a few key tools: an OBD-II scanner, a multimeter, and maybe a wiring diagram for your vehicle.
The OBD-II scanner is crucial because it reads the error code and gives you real-time data to identify the problem.
A multimeter helps you check the resistance and voltage in the glow plug circuit to make sure everything is working right.
The wiring diagram is useful for tracking down any electrical issues or damaged wires in the circuit.
Having these tools is important for a proper diagnosis so you can quickly find and fix what’s wrong.
Visual Inspection Steps
After getting your diagnostic tools, start by looking closely at the glow plugs and wiring harness for any obvious problems. Pay attention to these areas:
- Glow Plugs: Look for cracks or changes in color that might mean they aren’t working right.
- Wiring Harness: Check for wires that are frayed or connections that are loose.
- Connectors: Make sure there’s no rust or dirt affecting the electric contacts.
- Glow Plug Relay: Look for signs of overheating or physical damage.
These visual checks are important steps to find potential issues before you move on to more detailed diagnostics.
This careful approach helps you spot obvious problems early, saving you time and effort later.
Using an OBD-II Scanner
Using an OBD-II scanner helps you to read and understand the P0671 code accurately, so you can find out exactly what’s wrong with the glow plug control circuit. This tool uses OBD II technology to give you real-time information, making it easier to diagnose problems quickly. Modern scanners offer features like live data streaming, freeze frame data, and detailed code explanations.
Here’s a quick look at some key scanner features:
| Feature | Benefit |
|---|---|
| Live Data Streaming | Shows real-time engine information |
| Freeze Frame Data | Takes a snapshot of conditions when the fault occurs |
| Code Definitions | Gives detailed explanations for each code |
Using an OBD-II scanner helps you find the root cause of the problem quickly, saving you time and avoiding unnecessary repairs.
Testing Glow Plug Resistance
Testing the resistance of glow plugs helps ensure they’re working correctly. You’ll need a digital multimeter for this task. Here’s a step-by-step guide:
- Turn off the engine and disconnect the battery to ensure safety.
- Clean around the glow plugs to remove any dirt or debris.
- Disconnect the glow plug connector.
- Set your multimeter to measure ohms (Ω).
- Place one probe on the glow plug terminal and the other on the glow plug body.
- Check the resistance measurement and compare it to the specifications in your vehicle’s manual.
- Replace any glow plug that has a resistance reading outside the specified range.
- Reconnect the glow plug connectors and the battery once you’re done testing.
This simple process helps you keep your glow plugs in good working order.
Repair Options and Costs
Once you’ve checked the glow plug resistance and found out which parts are faulty, it’s time to look at your repair options and their costs.
You might need to replace the bad glow plugs, which usually costs between $200 and $500. If the wiring harness is damaged, you’ll need to fix or replace that too. A broken glow plug relay might also need replacing, adding to your bill.
In the worst-case scenario, you could end up needing a new PCM (Powertrain Control Module), which can cost over $1,000. The total cost will depend on your vehicle’s make and model, as labor charges and parts availability can vary.
Doing the repairs yourself can save money but requires some technical know-how. Also, check if your warranty covers any of these repairs to help reduce costs.
Preventive Maintenance Tips
Regularly checking your glow plug system is key to ensuring your engine starts smoothly in cold weather and avoiding the P0671 code. Here are some simple maintenance tips to keep your glow plug system in great shape:
- Look over the glow plugs and wiring: Regularly inspect them for any signs of wear or damage.
- Check the glow plug resistance: Use a multimeter to make sure each plug is working correctly.
- Examine relay and PCM connections: Ensure all electrical connections are tight and free from rust or corrosion.
- Replace worn-out parts right away: Don’t wait for parts to completely fail; replace them as soon as you notice any issues.
More OBD-II Codes
Frequently Asked Questions
Can Driving With a P0671 Code Cause Long-Term Engine Damage?
Driving with a P0671 code can harm your engine over time. It can lead to poor engine performance and even cause it to fail. Use diagnostic tools to find and fix the problem quickly to avoid more damage and keep your engine in good shape.
Are There Any Temporary Fixes for the P0671 Code?
To answer the question, you can try temporary fixes like using a block heater or diesel fuel additive. However, these won’t solve the underlying problem—it’s best to consult a professional for a permanent repair.
How Do Weather Conditions Impact the P0671 Code?
Weather can be tricky. When it gets really cold, it can make glow plug problems worse. This can make it harder for your diesel engine to start and might make the P0671 code issues more noticeable.
Is the P0671 Code Specific to Certain Diesel Vehicle Models?
The P0671 code can cause problems in many different diesel vehicle models, not just certain ones. It shows up in any model that has a glow plug system. It’s important to diagnose and fix this issue quickly to avoid engine damage and starting problems.
Can Aftermarket Glow Plugs Resolve the P0671 Code Efficiently?
You can fix the problem with aftermarket glow plugs if you’re sure they fit your vehicle. Aftermarket parts might be cheaper and easier to find, but always check the details to avoid more issues.
Conclusion
Imagine your engine as a symphony orchestra. When a P0671 code shows up, it’s like a key violinist playing out of tune, messing up the whole performance.
By quickly checking and fixing the problem with an OBD-II scanner and a multimeter, you make sure everything runs smoothly.
Just like a conductor needs every instrument to be in sync, your diesel engine needs each glow plug to work well to keep things running efficiently.
