Possible reasons for the automatic transmission jerking when the speed is turned on:
Mechanical problems:
* Worn or dirty friction discs: When worn or dirty, friction discs cannot engage properly, resulting in slipping and jerking.
* Faulty solenoids: Solenoids control the flow of transmission fluid into the automatic transmission. Faulty solenoids can cause the transmission to shift erratically and cause jerking.
*Low Transmission Fluid Level: Low fluid level can cause insufficient pressure and slipping of the friction discs.
* Clogged Transmission Filter: A clogged transmission filter can restrict fluid flow and cause jerking.
* Worn thrust bearings: Worn bearings can cause vibrations and jerking.
Electrical problems:
*Faulty Transmission Speed Sensor: A faulty sensor can provide incorrect data to the Transmission Control Module (TCM), resulting in incorrect shifts.
* Faulty TCM: The TCM controls the automatic transmission. A faulty TCM can result in improper shift control and jerking.
* Faulty Wiring: Damaged or faulty wiring can cause problems with signal transmission between the sensors and the TCM.
Other possible reasons:
* Worn spark plugs or ignition coils: This can lead to uneven combustion, which in turn can affect transmission performance.
*Dirty Throttle Assembly: A dirty throttle assembly can interfere with proper fuel metering, resulting in power fluctuations and jerking.
*Faulty Crankshaft Position Sensor: This sensor provides the TCM with information about engine speed and position that is necessary to properly control shifts.
Diagnosis and solution:
It is recommended that you contact a qualified mechanic to diagnose and correct the problem. They can do the following:
* Check the level and condition of the transmission fluid
* Test solenoids, sensors and TCM
* Inspect friction discs, support bearings and filter
* Eliminate any faults in electrical wiring
* Replace worn or faulty components