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Q: Idling and stalling

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When i start the car and let it idle it does its job perfectly. When driving i m ust maintain a high rpm greater than 1500 or it will stall. If i give it gas and maintain clutch control it is fine. As soon as the rpm drops below 1500 rpm the car stalls. What should i expect to replace?

My car has 135000 miles.
My car has a manual transmission.

Hi There, It sounds like you may have a MAP sensor that is malfunctioning as the reaction seems to correlate with the different loads put on the motor. The Manifold Absolute Pressure (MAP) sensor senses engine load and generates a signal that is proportional to the amount of vacuum in the intake manifold. The engine computer then uses this information to adjust ignition timing and fuel enrichment. When the engine is working hard, intake vacuum drops as the throttle opens wide. The engine takes in more air, which requires more fuel to keep the air/fuel ratio in balance. When the computer reads a heavy load signal from the [MAP sensor]((https://www.yourmechanic.com/services/manifold-absolute-pressure-sensor-map-sensor-replacement), it adjusts the fuel mixture to slightly more rich than normal so the engine can produce more power. The computer will then retard (back off) ignition timing slightly to prevent detonation that can damage the engine and decrease performance. This may also be caused by other closely related components such as a dirty or failing mass air-flow sensor, a faulty throttle position sensor or potentially a vacuum leak. I would recommend having an expert from YourMechanic come to your location to diagnose and inspect your vehicle.

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