Possible causes of vibration when the gear is engaged in a car with an automatic transmission:
Engine faults:
* Faulty spark plugs or fuel injectors
* Defective cylinders or valves
* Problems with the fuel injection system
* Worn ignition system
Transmission problems:
* Worn or faulty torque converters
* Failed transmission solenoids
* Leaking transmission fluid
* Worn transmission gears
* Incorrectly adjusted drive shaft
Drive problems:
* Worn or faulty CV joints
* Failed wheel hub bearings
* Improperly balanced tires or wheels
Other possible reasons:
*Failed flywheel
* Faulty or worn driveshaft
* Problems with the power unit (engine and transmission)
Diagnosis and elimination:
To diagnose the specific cause of vibration, you need to go through the following steps:
1. Vehicle Inspection: Visually inspect the vehicle for damaged or worn components such as tires, wheels and drive trains.
2. Scan Trouble Codes: Connect an ODB-II scanner to your vehicle to scan for trouble codes that may indicate engine or transmission problems.
3. Transmission Fluid Check: Check the transmission fluid level and condition. Low or dirty fluid may indicate a leak or wear.
4. Test Drive: Test drive the vehicle under various conditions to determine when and under what circumstances vibration occurs.
5. Separate Checks: Perform separate checks on the engine, transmission and drive to determine the source of vibration.
If the vibration is severe or cannot be corrected yourself, it is recommended that you contact a qualified mechanic for further diagnosis and repair.