PCV valve

Hi I have a  petrol 1.6vti.
The car was driving fine the only problem is giving out clouds of white smoke when pulling away form a stop start.
ie at the traffic lights or  junctions and so on. A friend said he thinks it was the PCV valve so we changed it he said drive the car let it clear itself it should be fine. The car was doing the same thing my friend said disconnect the breather pipe from the PCV valve and see what’s happens I’ve done that and the car drives perfect no smoke when pulling off from traffic lights or Junction. No problem lights on the dashboard and a car starts on the key drives perfect no lull in performance the only thing is if the car is standing in the same position ticking over for a few minutes when you pull away you get a great puff or  white smoke from the exhaust then it won’t do it again until you leave it to tick over and stand for a few minutes . But again ordinary pull off from the lights is fine no smoke only when it’s standing idling for 4/5 minutes I would like to know what is causing that ? And you can can smell exhaust fumes in the cab from time to time ( but the car does drive perfect with the hose disconnected starts on the key performance is normal no engine misfires no engine warning lights on dashboard just that big puff of smoke when idling too long