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Q: Oil Pressure fluke?

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When at a stop light today, when the light turned green and I put my foot on gas pedal at the same time the oil pressure light went on and the car died and was stuck there at the green light. I quickly turned off my car and started it back up with no problem, the oil pressure light went off as it normally does after starting the car and the car has been running fine the rest of the day. Was this a fluke?

A: The oil pressure most likely dropped as a r...

The oil pressure most likely dropped as a result of the engine dying simultaneously. The question is what caused the car to die upon takeoff? This may happen for many different reasons, however some of the common causes of this may be a dirty or faulty idle air control valve or a faulty throttle position sensor.

The idle air control valve reads the air intake as it is mixed with fuel prior to being injected into the engine at low speeds and at idle. Since this valve is controlled by the vehicle's computer, it will adjust idle speed based upon other measurements such as engine temperature, intake air temperature and electrical system load or voltage. When you accelerate, the engine RPM increases, and as you let off the gas, the RPM slowly returns to the normal idling speed with the help of the idle air control valve. When the engine RPM drops below the normal range of about ~800 RPM, this often times will cause the engine to stall indicating a dirty or faulty idle air control valve.

The throttle position sensor (TPS) is a sensor used to monitor the throttle position of the throttle plate inside the throttle body in relation to your foot position on the gas pedal. Based upon the inputs from the sensor reading your foot's position on the pedal, the ECU then makes the direction to supply more or less fuel to the motor. When this sensor is not working properly, this can cause intermittent responses when pressing the gas pedal. I would suggest having a professional from Your Mechanic come to you home to diagnose your car's running condition.

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