The P0086 trouble code is a diagnostic trouble code (DTC) that indicates an issue with the exhaust valve control solenoid circuit in bank 2 of a vehicle’s engine. This code is triggered when the Engine Control Module (ECM) detects high voltage or resistance in the circuit, suggesting that the solenoid is unable to function correctly. Understanding and addressing this code is crucial for maintaining optimal engine performance and avoiding further complications.
| P0086 Code Meaning | P0086 Code Common Causes |
|---|---|
| Exhaust Valve Control Solenoid Circuit High (Bank 2) | Faulty exhaust valve control solenoid |
| High voltage detected in the solenoid circuit | Damaged or corroded wiring or connectors |
| ECM unable to control exhaust valves properly | Failed Electronic Control Module (ECM) |
| Potential issues with variable valve timing (VVT) | Low engine oil level affecting VVT operation |
Symptoms of P0086 Code
When the P0086 code is present, vehicle owners may notice several symptoms, including:
- Check Engine Light: The most immediate indication of a problem, the check engine light will illuminate on the dashboard.
- Reduced Power and Performance: Drivers may experience difficulty accelerating or maintaining speed due to reduced engine power.
- Rough Running: The engine may run roughly, exhibit misfires, or have irregular idling, leading to an uncomfortable driving experience.
- Poor Fuel Economy: A noticeable drop in fuel efficiency may occur as the vehicle’s engine struggles to operate optimally.
- Engine Stalling: In severe cases, the engine may stall or fail to start altogether.
Technical Explanation of P0086 Code
The P0086 code specifically relates to the exhaust valve control solenoid circuit in bank 2. The exhaust valve control solenoid is part of the variable valve timing (VVT) system, which optimizes engine performance by adjusting the timing of the intake and exhaust valves. When the ECM detects high voltage in this circuit, it indicates a malfunction that can lead to improper valve operation.
The VVT system plays a critical role in improving fuel efficiency and reducing emissions by enabling more precise control over valve timing based on engine load and speed. If the exhaust valve control solenoid fails or if there are wiring issues, it can disrupt this process, leading to various performance issues.
Step-by-Step Diagnosis of P0086 Code
Diagnosing the P0086 code involves several steps:
- Scan for Codes: Use an OBD-II scanner to confirm that the P0086 code is present and check for any related codes that might provide additional context.
- Inspect Wiring and Connectors: Visually inspect all wiring and connectors associated with the exhaust valve control solenoid for signs of damage, corrosion, or loose connections.
- Check Voltage and Resistance: Using a digital multimeter (DMM), measure the voltage and resistance at the solenoid connector. Compare these readings with manufacturer specifications.
- Test Solenoid Operation: If wiring appears intact, test the solenoid itself by applying direct power to see if it operates correctly.
- Evaluate ECM Functionality: If all else checks out, consider testing or replacing the ECM as it may not be sending proper signals to the solenoid.
Solution Methods for P0086 Code
To resolve issues associated with the P0086 code, consider the following solutions:
- Replace Faulty Exhaust Valve Control Solenoid: If testing reveals that the solenoid is defective, replacing it is essential for restoring proper functionality.
- Repair or Replace Damaged Wiring: Address any wiring issues by repairing or replacing damaged sections to ensure proper electrical flow.
- Check Engine Oil Levels: Ensure that engine oil levels are adequate, as low oil can affect VVT operation. Top off if necessary.
- Reprogram or Replace ECM: In rare instances where the ECM is found faulty after testing, reprogramming or replacement may be required.
Cost Estimates
The costs associated with diagnosing and repairing a P0086 code can vary widely based on location and vehicle type:
- Diagnostic Fee: Expect to pay between $75-$150 for a professional diagnostic service.
- Exhaust Valve Control Solenoid Replacement: Parts typically range from $50-$200, while labor costs can add another $100-$300 depending on accessibility.
- Wiring Repairs: Minor repairs may cost around $50-$100, but extensive wiring issues could escalate costs significantly.
- ECM Replacement: This can be one of the more expensive fixes, ranging from $300-$1,000 depending on vehicle make and model.
Warnings and Recommendations
When dealing with a P0086 code:
- Do Not Ignore Symptoms: Ignoring warning signs can lead to more severe engine problems down the line.
- Professional Help May Be Necessary: If you are unsure about diagnosing or repairing electrical components, seek assistance from a qualified mechanic.
- Follow Safety Precautions: Always disconnect the battery before working on electrical systems to avoid shorts or shocks.
Frequently Asked Questions About P0086
- What does error code P0086 mean?
P0086 indicates a high voltage condition in the exhaust valve control solenoid circuit for bank 2. - Can I drive my car with a P0086 code?
While it may be possible to drive short distances, it’s advisable to address this issue promptly due to potential performance impacts. - What are common causes of P0086?
Common causes include a faulty exhaust valve control solenoid, damaged wiring, and low engine oil levels. - How do I clear a P0086 code?
The code can be cleared using an OBD-II scanner after repairs are made; however, ensure all underlying issues are resolved first. - Will replacing the solenoid fix my problem?
If the solenoid is indeed faulty, replacing it should resolve the issue; however, ensure that no other problems exist. - How much does it cost to fix a P0086 code?
The total cost can range from $150 to over $1,000 depending on parts needed and labor involved. - Is it safe to ignore a check engine light related to P0086?
No, ignoring this light can lead to further damage and increased repair costs. - Can I troubleshoot P0086 myself?
Yes, basic troubleshooting can be done at home; however, advanced diagnostics may require professional equipment.
In conclusion, understanding and addressing OBD-II trouble code P0086 is essential for maintaining your vehicle’s performance and reliability. By recognizing symptoms early and following proper diagnostic procedures, DIY mechanics can effectively troubleshoot this issue. However, when in doubt or faced with complex electrical problems, seeking professional assistance is always recommended.