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 a sensor in your car that measures air pressure isn't working right. It's like if you had a balloon and couldn't tell how full it was because your pressure gauge is broken.
The P1237 code indicates that the voltage signal from the secondary upstream manifold air pressure sensor is lower than expected by the engine control module (ECM).
The manifold air pressure (MAP) sensor is responsible for measuring the air pressure in the intake manifold. The ECM uses this data to adjust the air/fuel mixture for optimal engine performance. A 'circuit low' condition means the sensor is sending a voltage signal that is below the normal operating range, which can affect engine performance.
• Check Engine Light is on
• Poor engine performance
• Increased fuel consumption
• Faulty manifold air pressure sensor
• Wiring issues such as shorts or open circuits
• Faulty ECM
ECM: Engine Control Module
MAP Sensor: Manifold Air Pressure Sensor
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors to the MAP sensor for damage.
• Test the MAP sensor voltage output with a multimeter.
• Replace the manifold air pressure sensor.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Screwdriver set
$100 - $300
Moderate
• Ford Focus
• Chevrolet Silverado
• Toyota Camry
• Regularly inspect and maintain engine sensors.
• Ensure wiring and connectors are secure and undamaged.
• Keep the engine clean to prevent debris build-up.
Sensor Issue
• Address the issue promptly to avoid further engine problems.
• Consult a professional mechanic if unsure about repairs.
Check with your vehicle manufacturer for warranty coverage on engine sensors.
This code has been associated with sensor failures in various models, often due to wear and tear over time.
Moderate – This issue should be addressed soon to prevent potential engine performance problems.
Driving with a faulty sensor can lead to increased emissions and potential engine damage.
• Engine running
• Vehicle at operating temperature
The manifold air pressure sensor is typically located on the intake manifold near the throttle body.
Q: Can I drive with a P1237 code?
A: While you may be able to drive with this code, it's not recommended as it can lead to poor engine performance and increased emissions.
Q: How do I clear a P1237 code?
A: After fixing the issue, you can clear the code with an OBD-II scanner.
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