2006 Kia Sorento 4X4, Diesel. Starts right up but runs "rough" (more vibration than normal and valves rattle at low revs) and produces great deal of white smoke until engine heats up (after about 2-3 minutes of operation). Once engine is heated up it stops producing white smoke but exhaust still smells very strongly, as if diesel is not combusting properly? Engine valves continue to rattle at low revs. Any ideas?

I take that back about EGR, but I still think it makes no sense to look for problems with an EGR valve just because you see smoke in the exhaust. I take that back about EGR, but I still think it makes no sense to look for problems with an EGR valve just because you see smoke in the exhaust.

Just to clarify things for others: Diesel motors have glow plugs instead of spark plugs. They get hot like a filament in a light bulb. When the cylinder is filled with diesel mist and air, then compressed to a very high ratio, it ignites where the glow plug is. Not the same as a gas motor needing a spark instead of compression to ignite. Just to clarify things for others: Diesel motors have glow plugs instead of spark plugs. They get hot like a filament in a light bulb. When the cylinder is filled with diesel mist and air, then compressed to a very high ratio, it ignites where the glow plug is. Not the same as a gas motor needing a spark instead of compression to ignite.