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's engine isn't getting the right amount of air pressure when the car is idling, like when you're stopped at a red light.
The P1240 code indicates that the secondary manifold air pressure sensor is detecting a lower than expected pressure reading when the engine is idling.
The secondary upstream manifold air pressure sensor is responsible for measuring the air pressure in the intake manifold. This information is used by the engine control module (ECM) to adjust fuel delivery and maintain optimal engine performance. When the sensor signal is too low, it may indicate a problem with the sensor itself, a vacuum leak, or an issue with the wiring or connectors.
• Check Engine Light is on
• Rough idling
• Poor fuel economy
• Faulty manifold air pressure sensor
• Vacuum leak in the intake manifold
• Damaged or corroded wiring/connectors
Manifold: A pipe or chamber branching into several openings.
Sensor: A device that detects or measures a physical property and records, indicates, or otherwise responds to it.
• Use an OBD-II scanner to confirm the code
• Inspect the manifold air pressure sensor and its wiring
• Check for vacuum leaks in the intake manifold
• Replace the faulty manifold air pressure sensor
• Repair or replace damaged wiring/connectors
• Fix any vacuum leaks
• OBD-II scanner
• Multimeter
• Vacuum leak detector
$100 - $300
Moderate
• Ford Focus
• Chevrolet Cruze
• Toyota Camry
• Regularly inspect and maintain engine sensors
• Check for vacuum leaks during routine maintenance
• Ensure electrical connections are clean and secure
Sensor Issue
• Have the vehicle inspected by a professional if the Check Engine Light is on
• Avoid driving for extended periods with the Check Engine Light on
Check with your vehicle manufacturer for warranty coverage on engine sensors.
This code has been associated with issues in vehicles with complex intake manifold systems, particularly in models with turbocharged engines.
Moderate – While the vehicle may still be drivable, it is important to address this issue to prevent further engine performance problems.
Driving with a malfunctioning engine sensor can lead to increased emissions and potential engine damage.
• Engine idling
• Normal operating temperature
The manifold air pressure sensor is typically located on or near the intake manifold.
Q: Can I drive with a P1240 code?
A: It's possible to drive for a short period, but it's not recommended as it may lead to further engine issues.
Q: How can I prevent a P1240 code?
A: Regular maintenance and inspections can help prevent sensor-related issues.
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