My polo is not starting well when cold. The glow plug light comes on briefly, but when the car is started it takes a few seconds to start and emits lots of white smoke. There is no problem starting when the engine is warm The VW dealer (obviousely) wants me to book it in for them to check and says it will either be a faulty temperature sensor or faulty glow plug. One other complication though, I broke down a few weeks ago and the garage I was towed to checked out the electrics (amongst other things) and I think this has been happening since then (the car was fine to start when I picked it up, but I didn't use it again for 2 weeks as I went straight on holiday). It may just be a coincidence, but does anyone know of anything that they may not have connected back up properly that could cause this problem?