QUOTE(billyykl99 @ Mar 26 2020, 03:46 PM)
Hi guys, im currently driving an avanza 1.3 2004
Recently i found that my gearbox is jerky even though i serviced well and this time i did put a bottle of gearbox treatment.
Problem:
Shaking and jerky while changing from 1st to 2nd gear sometime to 3rd gear
Is it the problem caused by the failure of transmission filter?
Can you describe further how does the jerking and shaking happen? (i.e. during idling/traffic light, or as building up speeds?)
If you kept it in just one gear, e.g. 1st gear, does the problem still happen?
The last time I had something like this happening to me was at a certain RPM and the cause was the VVTI actuator.
In technical terms, the mechanic explained to me at high RPM when the VVTI advanced, a rubber piece broke and this does not allow the VVTI actuator to retard when the loud pedal was lifted off.
In this sense, when I were to take off from a traffic light, my car would be at the wrong timing and would be spluttering along the way and gets smoother as RPM builds up. Once the car shifts from 1st gear to 2nd gear, the RPM drops and I start to splutter again until RPM builds up.
If yours is the same like mine, try to get the mechanic to look at the VVTI actuator to see if any rubber piece has broken off or got stuck there.