Porsche 911UK Forum

Welcome to the @Porsche911UK website. Register a free account today to become a member! Sign up is quick and easy, then you can view, participate in topics and posts across the site that covers all things Porsche.

Already registered and looking to recovery your account, select 'login in' and then the 'forget your password' option.

White Smoke From Exhaust on Start Up

WasteGate

New member
Joined
25 Feb 2017
Messages
3
I have a Low Mileage 1991 Porsche 965 (Turbo). Plenty of Oil Pressure at normal Operating Temperature and performs brilliantly. The car has been kept in my garage unused (on the road) for around two years. I start up the car regularly to keep the Oil Circulating and stop the Oil Seals from drying out. I started the car up today and masses of white smoke was being pumped out of the Exhaust. I let the car run up to Operating Temperature as normal but the thick white smoke was still being pumped out. l calmed the neighbours down and assured them there wasn't a fire - kind of them to ask. I shut the engine down and made a coffee while the white smoke cleared. After 20 minutes or so, l started to car up again and,,,,,,,,,,,,,NO MORE WHITE SMOKE - Hallelujah !!! What was going on ???
 
When the car sits for a length of time, oil will migrate into the cam covers/ valve gear. When this happens often it get sucked through the valve seals and burns off in the combustion chambers, hence white smoke.

Can also be classic oil overfill being burned off if you have recently topped up the oil. :thumb:
 
Also it's not a good idea to just keep starting the car up and not driving it. More wear is done. Better to leave it be then after several months pull the DME relay to build oil pressure first as you turn it over. Replace DME then fire it up :thumb:
 
Chief's correct, a common issue.
Rothsport make a one way valve which fits in the oil line and prevents this, you'd need to check that the fitment is correct for your car though.
It's also bloody expensive for what it is IMO at $300 + shipping +rip off import tax.
I'd be surprised if you also don't have oil dripping onto your heat exchangers as the lower rocker area will be full of oil and the valve covers are not the best at sealing.

Best preventative measure, take it for a drive at least once a week .... Says me who's done around 10K in 11 years in mine.
 
Thanks to everyone for all the very helpful suggestions concerning the possible cause/s of the White Smoke at start-up.

Since the initial time this had happened, l have started up the car and everything appears absolutly fine - no sign of white smoke and no sign and/or smell of burning oil and perfect, smooth running at Tickover.

The Oil Level is perfect at full engine working temperature and l have since thought the problem might have been caused by a small amount of Power Steering fluid leaking from the Pump and running down the Flexible Hose which connects to the Power steering Reservoir which sits above the right-hand Heat Exchanger - the Chassis Member is a little wet in this area.

The PS Reservoir had needed Topping Up after a run on a couple of ocassions.

Lets hope this is the cause - l will keep the Forum informed.

And, once again, a Big Thanks again for all the interest shown and the time taken to Post suggestions !!!

I will now concentrate on getting the Beast out for a long run at speed and clear its lungs out - YES, Porsches really DO need to be driven !!!
 
Would it not have been 'light blue' smoke if it was oil burn.
If as the OP has indicated, by starting up and allowing the car to tick over/warm up stationary; could it not be an accumulation of condensation? Hence white smoke!
Just a suggestion ;)
 
Lot to do with outside air temperature , tend not to show much smoke when the weather is warm but they always produce white smoke on start up even if used every day , soon disappears as the engine is warms up .
 
Hi, oil or PS fluid dripping onto the heat exchangers will generally cause a mist of smoke to waft out from the rear wheel arch area, it won't cause as you described "masses of white smoke to be pumped out of the exhaust"
Smoke coming out of the exhaust has to have come from the combustion process from within the engine.
Anyway you said it's not doing it anymore so hopefully all's well
 

New Threads

Forum statistics

Threads
124,350
Messages
1,439,432
Members
48,707
Latest member
race911turbo
Back
Top