So yes, posting here as a new topic for the first time, i bought ES MIRA 2012/2015 last year in February, the car ran brilliant for first few months, i never saw its auction sheet as i bought it from a dealer and it was already registered, 17k on ODO at that time, i knew the meters usually get reversed, first oil i poured in was shell hx7 5w30, then i went for fuchs 5w30 and now using Liqui Moly 0W20, the problem i am facing is sluggishness and jerks under 25km/h, the car vibrates when stopped at signal or at 2, 3 km/h speed, during AC the vibration can be felt a little more than usual, i have got almost everything that my mechanics and some experts suggested, i did came close to the solution but not there yet. Throttle Body serviced, (taking out the butterfly itself, spraying carburetor spray on the throttle everything) got my map sensors serviced and Oxygen sensors too, changed transmission fluid, transmission mount and engine mount, recently got my catalytic converter replaced following some experts opinion, as far as i searched my original catalytic converter isnt completely choked or anything but yes i still replaced it, but jerks, sluggishness still exists, i just checked my engine oil level and found out that my engine oil has turned dark brown and the level is also gone down to half, i have hardly completed 4 months and 3200kms on this oil with 2 air and oil filters, this has never happened, sometime i also think that i dont know how much my car is driven in actual as the ODO meter said 17k when i bought and now i have completed 28k, i need some serious help regarding my car problems, i would appreciate an expert help as i have spent thousands and my precious time fixing my problem.