Ever since the temperatures dropped (they are about 18*C in my garage so I wouldn't classify them as low) I started noticing the engine takes a few cranks to start. When I take the car out of the garage and the temperature is around 5-10*C, there is white smoke coming out of the exhaust the first 5-10 minutes until the engine warms up. From what I've read this is a sign of an issue with the preglow system - either the relay or the glow plugs. I checked the car on a Star Diagnostic tool but it shows no errors. What do you guys think?