Engine-Codes.com
Engine-Codes – Generic – P1387

P1387 Code - Control Unit Internal Altitude Sensor

Quick Answer

The P1387 code indicates a problem with the control unit internal altitude sensor in the vehicle. Common causes include Faulty altitude sensor, Wiring or connection issues, Corrosion or damage to sensor components. 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
P1387 indicates Control Unit Internal Altitude Sensor.
Common causes
Common causes include Faulty altitude sensor, Wiring or connection issues, Corrosion or damage to sensor components.
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 06, 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 P1387 Description

The P1387 code indicates a problem with the control unit internal altitude sensor in the vehicle. This sensor is responsible for measuring the altitude at which the vehicle is operating, allowing the engine control module to adjust fuel delivery and ignition timing accordingly. When this sensor malfunctions, it can lead to incorrect fuel and ignition settings, resulting in poor engine performance, reduced fuel efficiency, and potential drivability issues. If left unaddressed, this issue can cause long-term damage to the engine and other related systems.

OBDII Code P1387 - Control Unit Internal Altitude Sensor
P1387 Code - Control Unit Internal Altitude Sensor

Common Causes of P1387

  1. Faulty altitude sensor
  2. Wiring or connection issues
  3. Corrosion or damage to sensor components
  4. Electronic control module malfunction
  5. Environmental factors affecting sensor accuracy

Symptoms of P1387

  1. Reduced engine performance
  2. Poor fuel efficiency
  3. Rough idling or stalling
  4. Illuminated Check Engine Light
  5. Difficulty starting the vehicle

How to Fix P1387

  1. Diagnose the issue using a diagnostic scanner to confirm the P1387 code.
  2. Inspect the altitude sensor and its wiring for any damage or corrosion.
  3. Replace the altitude sensor if it is found to be faulty.
  4. Clear the error code and test drive the vehicle to ensure the issue has been resolved.
  5. If the problem persists, further diagnostics may be required to identify any underlying issues with the control unit or other related components.

Cost to Fix P1387

The typical repair costs for addressing the P1387 code can vary depending on the specific make and model of the vehicle, as well as the location and labor rates of the auto repair shop. In general, the repair for this issue may range from $200 to $500, including parts and labor. It's recommended to obtain quotes from multiple reputable auto repair shops to compare prices and ensure a fair cost for the repair.

Need more information about the P1387 code?

Need more information on how to fix the P1387 code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P1387 code diagnosed by a professional: Find a repair shop in your area

Code P1387 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 P1387 Code

1. What does the OBDII code P1387 mean?

P1387 indicates a fault with the control unit's internal altitude sensor, which monitors air pressure to adjust engine performance at different elevations.

2. What are the common symptoms of code P1387?

Symptoms may include reduced engine performance, poor fuel efficiency, difficulty starting the engine, or the check engine light being illuminated.

3. What causes the P1387 code to appear?

The code can be triggered by a faulty altitude sensor, wiring issues, a malfunctioning control unit, or contamination inside the sensor.

4. Can I drive my car with the P1387 code active?

While the car may still be drivable, it can experience reduced performance and efficiency. Prolonged driving without addressing the issue may lead to further engine or sensor problems.

5. How is the P1387 code diagnosed?

A technician will typically use a scan tool to verify the code, inspect the wiring and connectors, and test the altitude sensor's functionality.

6. What repairs can fix the P1387 code?

Repairs may include replacing the altitude sensor, repairing or replacing damaged wiring, or reprogramming or replacing the control unit.

7. Is the P1387 code specific to certain car models?

While it can occur on various vehicles, the specifics of the code and related components may vary by manufacturer. Always consult your vehicle's repair manual.

8. How much does it cost to fix the P1387 code?

Repair costs depend on the root cause but typically range from $100 to $500, including parts and labor.

9. Can a dirty air filter cause the P1387 code?

No, a dirty air filter does not directly cause this code, as it relates to the control unit's internal altitude sensor, not the intake air system.

10. How can I prevent the P1387 code from recurring?

Regular maintenance, keeping electrical connections clean and secure, and addressing sensor issues promptly can help prevent the code from recurring.

Discuss the causes and fixes for P1387 OBDII Code

Submit a New Comment

Code P1387 comments

No comments found for this page.