if ur car is blowing smoke...generally that isn't a good sign...one...it could be ur turbo going dead....or two...u could have a blown headgasket.....but either way....u need to get it looked after....i wouldn't drive the car much to prevent further damage......
"safe mode" will happen whenever:
*You have the check engine light on
*The ECU detects knock
*Your coolant is not up to temp
*Ambient temps are too low
If you are smoking, you have bigger issues than being in "Safe mode"