people dun simply tambah engine oil...
ur oil level should be in the range between the LOW and HI mark of ur dipstick..
normally ppl will put until the HI mark...
if u need to tambah from time to time.. means ur car drinking oil liao.. means dat piston ring worn out...
for ur case.. i think is overflow liao.. dat y ur endine is sluggish.. the oil too full n the oil create a lot of resistance...