Q: On slow moving traffic, when i release the brakes, the car has lags for half a second before take off... computer scan shows p2138

asked by on October 12, 2016

i had a gear box issue, i replaced it, the car now drives well, but during traffic takeoff while on D, the car hesitates for half a second and then drives on normally, a computer scan showed p2138, it was cleared but the car still has the above problem... what could be issue?

My car has 84000 miles.
My car has an automatic transmission.

This code is related to a faulty throttle position sensor. The throttle position sensor (TPS) is a sensor used to monitor the throttle position of a vehicle. The sensor is usually located on the butterfly spindle/shaft so that it can directly monitor the position of the throttle. This sensor relays the position of the throttle plate (also called the butterfly) relative to your foot’s position on the gas pedal and associates the two in the ECU. 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 applying the gas pedal. I would suggest having a certified professional, like one from YourMechanic, come to your home to diagnose your Check Engine Light firsthand and replace this sensor as necessary.

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