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Q: Shifts in high rpm at very low speeds

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Two days ago I noticed my car shifted aggressively and then it would jerk my car a lil. One day ago the problem got worse and it still shifts your rpm at very high Rpms. Around 3,000. When I drive it shifts quickly into first and revs high on 2nd and 3rd gear. Just put some new oil in cuz it was low. Not sure if it was because it was low on some oil. It wasn't too low but didn't realize it was this bad. Any suggestions. Can I get it coded for problems?

My car has 142000 miles.
My car has an automatic transmission.

What you are describing may be a result of a faulty speed sensor, potentially low transmission fluid or a even a faulty transmission control solenoid. As your vehicle travels down the road, the computer analyzes data being sent by vehicle speed sensors and engine speed sensors. Based on this information, the Engine Control Unit (ECU), or the Transmission Control Unit (TCM), executes the appropriate upshifts and downshifts by sending a signal to one of several shift solenoids. These transmission solenoids have spring-loaded plungers inside them, which are wrapped with wire. When this coil of wire receives an electrical charge from the TCM / ECU, it causes these plungers to open, allowing transmission fluid to flow into the valve body and pressurize the desired clutches and bands. When this happens, the transmission changes gears and you continue down the road. The computer controls the transmission solenoid in several ways. If the vehicle is equipped with a dedicated Transmission Control Unit, it can open or close the hydraulic circuit using a direct 12v signal. In some cases, the Engine Control Unit (ECU) can control the solenoid’s plunger by turning the ground circuit on and off. When this is not working properly, this can cause a jerking reaction, a delay in shifting or in some cases may cause the transmission to hesitate in shifting gears. I would recommend having a professional from YourMechanic come to your location to diagnose and inspect your transmission.

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