Thanks Brother for the response i just bought this car and its was not giving any smoke or i have not seen smoke at the time of purchasing, i have change its spark plug also put 5w30 shell oil now initially mechanic put some zic oil which one he put i dont know exactly, but once i saw the smoke on heavy throttle i immediately visit to another mechanic and he told me to used only recommended oil only, however its not giving any smoke on moving condition, now i am worried that is its engine is week or there is some thing else, as i am totally unaware of vitz mechanism.