Hello!I got Nissan Sentra B14,when I stop at traffic light and the time ready to go,I press bit harder on fuel paddle as I insert 2nd and 3rd gear,there is some white smoke came out from the car exhaust,the funny thing is,the white smoke is not contineous,it just blow out for 2 or 3 second,then the car would go smooth without smoke.....I wonder perhaps the piston ring had wore out or the inner engine part had too dirty,cos I am now using STP Oil Treatment,some mechanics said oil treatment can help to clean out the inner engine part,the deposit which stick inside engine would wash away bit by bit and then blow out through the back exhaust...Guys,do you have any idea instead of changing a new engine or go for overhaul??...Is there any better oil treatment in the market can really stop the smoke?Or should I try STP Motor Flush to wash the engine while I go for service,or maybe the valves or curb have to be clean up??Lastly to inform I am now using Caltex techron black oil,is any better black oil in the market can help in this matter?Thanks guys for yours' reply!!!