I have a Golf Mk4 1.9 TDI 150 diesel which generally performs fairly well but, from cold, especially after a cold night, emits white smoke and smells of diesel fuel. All seems fine when it warms up. It is less obvious in the summer. The engine is not especially noisy and fuel economy seems reasonable as well. Any suggestions as to what to do next? I would be more than happy to seek advice from a local garage if I thought that they knew more than me and did not rely on guesswork. I live in Yeovil in Somerset, so any thoughts about an expert within a reasonable radius would also be very welcome. Thanks for your time.
You don’t mention how smoothly the car runs on start-up, but white smoke often means a failed glow plug, with that cylinder not firing properly, but improving with warm-up. Or alternatively it might be water in the fuel, probably from a failed head gasket. In reverse order to the above, unscrew the oil filler cap and look for any white “mayonnaise” of oil and water that could result from a cylinder head leak, and unscrew the cap (when engine cold) and look in the coolant header tank for any traces of oil. A cylinder compression check would give further evidence on this, but you’ll really need a garage electrician to check the glow plugs out. Otherwise, it could be worn/dirty injector problems, giving a poor spray pattern and unburnt fuel, but check the first two suggestions before you explore the others. I would appreciate hearing how you get on with these suggestions.
DCB Autos on Lynx Trading Estate, Yeovil get consistently excellent customer reports. I would try them first. Heritage Skoda in Yeovil are also well spoken of, but being a Skoda franchise will be more costly, if maybe better equipped. Hope that I’ve been of some assistance.