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Q: Rpm fluctuates car will not shift out.

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The rpm fluctuates while driving and the car wont shift out.

My car has 88000 miles.
My car has an automatic transmission.

Hi There, Your RPM fluctuation may be a result of a faulty mass air flow sensor or idle air control valve. As a result of this, your transmission control module may have trouble indicating shift points. This may be impacted directly by the RPM fluctuation or potentially by a faulty control module. The transmission control module has various sensors such as vehicle speed sensors, wheel speed sensors, throttle position sensors, turbine speed sensor, and transmission fluid temperature sensors that all direct information to it in order for it to perform it’s function. Other functions controlled by the TCM are components such as a kick down switch, traction control system, and cruise control module. Any of these may also affect the way the transmission control module performs and controls the transmission and the shifting of your vehicle. A faulty transmission control module may cause also cause a delay in acceleration or erratic shifting of gears. I would suggest having a professional from Your Mechanic come to your location to properly diagnose your transmission problem.

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