Leadingshield

Newbie here who has just gone through the same problem. I have a 2006 Aurion, only done 55000km and had the same white cloud of smoke upon start up and if I had left the car sitting for more than an hour or so, it also started smoking when I turned a sharp left hand turn and accellerated out of the corner???? Was told by many that it was probably valve stem seals.........until I came across a mechanic who actually took the time to research the net and start at the obvious!! As it turns out, it was, as is this case, related to a big build up of sludge in the system which in turn had blocked the PCV valve open, which in turn allowed oil to be sucked into the intake manifold which sat there and was ready to blow a big cloud of smoke when vehicle was started up. The PCV valve was cleaned and replaced which allowed the motor to breath as it should, but because of the high sludge build up in my motor, the possibility of the PCV Valve blocking again was inevitable, so to help as a temporary fix, the mechanic also fitted a by-pass can from the PCV Valve to the intake which helped to catch any oil before it got to the intake should the valve block again (which it did). To permanently fix the problem, the rocker covers and sump had to be pulled off and the thick, licorice lick sludge was removed, the oil pick up was thoroughly cleaned, everything was assembled and then a new oil filter put in, a high detergent oil was added, then the vehicle was run for a week, with no smoke issues. After a week, 500ml of diesel fuel was added to the oil and the vehicle was started and left to idle for 15 mins, the oil was then drained (and it was reasonably black from the small amount of sludge left in the motor) the filter was taken out and replaced and then a high quality oil....Castrol Magnatec 10w-40w was used. This was a week ago and I have not had any more problems with smoke and the by-pass can is still there just in case, but I have never had to empty it since the majority of the sludge was removed. The PCV valve has not blocked up again...........YET!!!! Why Diesel in the oil some of you may ask ???? Diesel is a high detergent fuel and does not act as a solvent in your engine like commercial "Engine Flush" treatments, therefore is not detrimental to your engine. This is an old-time trick passed onto me by an elderly gentleman who also used to add diesel into his fuel tank to act as an upper cyclinder lubricant.....of course his car used to use standard petrol. Should you wish to take this route in fixing your vehicle, just be prepared to spend a fair amount of time and cleaning solution to clean your left hand rocker cover where the PCV valve is located as the baffle around the valve is not removable and this is where you need thorough cleaning, so do as I did and fill the baffle area through the PCV valve opening (with the rocker cover upside down) and prop the cover up so it doesn't fall over or let too much cleaning solvent out and just let it sit for 15 mins or so, then place a finger over the pcv valve hole and shake the fluid around to loosen up the sludge, then drain and blow out using a compressor and repeat as much as is needed until you see very little sludge coming out from under the baffle and the cleaning solvent is reasonably clean. I hope this helps not only for the person with this problem, but any future people who may have smoke problems. The cause of this costly exercise............using cheap oil......not having regular services and driving short distances on a daily basis!! As the saying used to go........"Oils ain't Oils Sol!!"