P0108 Technical Description
Manifold Absolute Pressure/Barometric Pressure Circuit High Input
In this guide, you’ll learn what the P0108 trouble code means, its symptoms, causes, and how to fix it. You’re likely here because your car’s throwing this code and you need solutions.
I’ve fixed this issue countless times, so you’re in good hands.
We’ll cover the technical details, common symptoms like poor fuel economy, and easy-to-follow fixes to get your car running smoothly again.
Alright, let’s get into it.
Key Takeaways
- The P0108 code signals a high voltage input from the MAP sensor.
- Symptoms include poor fuel economy, rough idling, and reduced engine performance.
- Common causes are faulty MAP sensor, wiring issues, and vacuum leaks.
- Diagnosing involves checking the sensor, wiring, and intake manifold for issues.
- Cleaning or replacing the MAP sensor often resolves the problem.
- Ignoring this code can lead to more serious engine issues over time.
Table of ContentsShow
What Does P0108 Trouble Code Mean?
The P0108 trouble code means the Engine Control Unit (ECU) has detected a high voltage signal from the Manifold Absolute Pressure (MAP) sensor.
The MAP sensor measures the pressure within the intake manifold, providing critical data to the ECU to manage fuel delivery and ignition timing accurately.
When this sensor sends a voltage signal that is higher than expected, it indicates there’s a problem.
Normally, the MAP sensor voltage ranges between 1 to 4.5 volts, depending on engine load and speed.
A high voltage signal, typically above 4.5 volts, suggests either an issue with the sensor itself, a wiring problem, or a fault in the ECU.
The MAP sensor helps the ECU determine the engine load by measuring the air pressure in the intake manifold.
This data is crucial for adjusting the air-fuel mixture for optimal performance and fuel efficiency. If the MAP sensor sends incorrect data, it can lead to poor engine performance, increased emissions, and reduced fuel economy.
A high voltage signal might be caused by several factors. It could be a short circuit in the sensor wiring, a faulty MAP sensor, or an issue with the ECU.
Additionally, a vacuum leak or blockage in the manifold can also cause the MAP sensor to read incorrectly.
Understanding the P0108 trouble code is essential for diagnosing and fixing the underlying issue. Ignoring this code can lead to more significant engine problems over time.
If you’re seeing this code, it’s crucial to address it promptly to ensure your vehicle runs smoothly and efficiently.
P0108 Trouble Code Symptoms
When the P0108 trouble code appears, your vehicle may exhibit several symptoms. Here’s what to look out for:
- Check Engine Light illuminated
- Poor fuel economy
- Rough idling
- Engine hesitation or stalling
- Difficulty starting the engine
- Reduced engine performance
- Black smoke from the exhaust
- Increased emissions
P0108 Trouble Code Causes
Several issues can trigger the P0108 trouble code. Here are the most common causes:
- Faulty MAP sensor
- Short circuit in the MAP sensor wiring
- Damaged or corroded connectors
- Issues with the ECU
- Vacuum leak in the intake manifold
- Blockage in the intake manifold
- Faulty throttle position sensor
- Carbon buildup on the MAP sensor
How To Fix A P0108 Trouble Code
Fixing a P0108 trouble code involves diagnosing the root cause and then addressing it. Here’s a step-by-step guide to help you through the process:
1. Check the MAP Sensor and Wiring
Inspect the MAP sensor for any visible damage or corrosion. Ensure the wiring and connectors are secure and free of damage. Look for frayed wires or loose connections.
2. Test the MAP Sensor
Use a multimeter to check the sensor’s voltage. With the ignition on, the voltage should be between 1 and 4.5 volts. If it’s outside this range, the sensor may be faulty.
Compare the sensor’s readings to the manufacturer’s specifications. If it’s not within range, consider replacing the sensor.
3. Inspect for Vacuum Leaks
Check the intake manifold and vacuum lines for leaks. Listen for a hissing sound or use a smoke test to find leaks. Repair any vacuum leaks by replacing damaged hoses or gaskets.
4. Clean the MAP Sensor
If the sensor is dirty, clean it with an appropriate electronic cleaner. Ensure it’s dry before reinstalling.
5. Check the Throttle Position Sensor
Inspect the throttle position sensor (TPS) and its wiring. A faulty TPS can affect the MAP sensor readings.
6. Scan for Additional Trouble Codes
Use an OBD-II scanner to check for additional trouble codes. Address any other codes that might be related to the MAP sensor.
7. Inspect the ECU
If all else fails, there may be an issue with the ECU. Consult a professional to test and possibly reprogram or replace the ECU.
By following these steps, you can diagnose and fix the issue causing the P0108 trouble code. If the problem persists, seeking professional assistance is recommended to avoid further damage to your vehicle.
Conclusion
Now you know what the P0108 trouble code means and how you can fix it.
Got any stories about dealing with a faulty MAP sensor?
Drop a comment below and share your experiences!
