Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that the car's computer thinks the air pressure in the engine is not right. It's like when you blow up a balloon and it doesn't feel like there's enough air in it.
The Engine Control Module (ECM) has detected that the manifold absolute pressure (MAP) sensor is reporting a pressure reading that is not plausible based on other sensor data.
The P129E code is triggered when the ECM receives a signal from the MAP sensor that indicates a pressure reading below the expected range. This could be due to a faulty sensor, wiring issues, or an actual problem with the engine's air intake system.
• Check Engine Light is on
• Poor engine performance
• Engine may stall or hesitate
• Faulty MAP sensor
• Vacuum leak in the intake manifold
• Wiring issues or poor electrical connections
MAP Sensor: Manifold Absolute Pressure Sensor, measures the pressure inside the intake manifold.
ECM: Engine Control Module, the computer that manages engine functions.
• Use an OBD-II scanner to confirm the code.
• Inspect the MAP sensor and its wiring for damage.
• Check for vacuum leaks in the intake manifold.
• Replace the MAP sensor if faulty.
• Repair or replace damaged wiring.
• Fix any vacuum leaks found in the intake manifold.
• OBD-II scanner
• Multimeter
• Vacuum gauge
$100 - $300
Moderate
• Chevrolet Silverado
• Ford F-150
• Toyota Camry
• Regularly inspect and maintain the intake system.
• Ensure all sensors are clean and functioning.
• Check for and repair any vacuum leaks promptly.
Sensor Issue
• Have your vehicle checked by a professional if you see this code.
• Do not ignore the Check Engine Light, as it could lead to more serious issues.
Check with your vehicle manufacturer for warranty coverage on emissions-related components.
This code has been associated with sensor issues and intake system problems in various vehicles.
Moderate – It's important to address this issue to prevent further engine performance problems.
Driving with a malfunctioning MAP sensor can affect vehicle emissions and may not comply with local regulations.
• Engine at operating temperature
• Vehicle in a safe, stationary position
The MAP sensor is typically located on or near the intake manifold.
Q: Can I drive my car with a P129E code?
A: It's not recommended to drive for extended periods with this code, as it can affect engine performance and emissions.
Q: How can I prevent a P129E code?
A: Regular maintenance of the intake system and ensuring all sensors are in good condition can help prevent this code.
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