Why is there white smoke coming from my Porsche Boxster’s exhaust?

The most likely cause of the smoke is failure of the air-oil separator - a device designed to reduce the Porsche Boxster’s emissions. This can result in oil being sucked into the intake manifold, causing damage to spark plugs and the catalytic convertors.

An air-oil separator failure may trigger a ‘check engine’ light or a squealing noise from the engine, but the most common symptoms are large amounts of white smoke coming from the exhaust and the engine running roughly.

Given that the problem can lead to damage to more expensive parts, it is sensible to seek advice from a Porsche specialist and, if necessary, get the air-oil separator replaced as soon as you notice the issue.