Help please! Advice! Guidance! Experience!

Hi newby here, I have an Audi A3 1.9 tdi on a 2007, The problem being is there’s a cloud of white smoke from cold no matter the weather, the smoke lasts for a minute or so then disappears once the cars up to a certain temperature, never any smoke when warm driven at idle standstill, leave the car for a good few hours and it returns again! I’ve replaced all 4 glow plugs, replaced the glow plug relay, fuel filter, rebuilt injectors (new o rings & base copper washer) fitted with a kit so no pinching of o rings, set the back lash correct 180 turn back, checked tortion value timing on vagcom it’s 0.5 so ok? Injectors are reading 0.49mg 0.02mg 0.66 & 1.20 so are within tollorance? So injectors seem ok, timings ok, I’m sure there’s others I’ve missed out but could anyone give me advice, or other thinks to check please, thanks

Only thing I can think of is to unplug the maf and see if it changes anything.

Are you sure it isn’t steam?

How many miles on the car? If it's a lot it could be oil leaking down into the combustion chambers when the car sits. That'll give you a good cloud of white smoke on cold startup. Once the engine is warm, expansion stops the leak down, so you don't see smoke then, nor would you necessarily seen any significant oil consumption. It doesn't take much oil to make quite a bit of smoke.

Hi 100,000

Hi it never used any oil at all and I’ve marked the header tank and it’s not used a drop of coolant in 6 months

Just an update, I’ve tried all the things you can see in the post & more, anyway I thought I’d check to see if the turbo seals were shot as there might be oil blown in the pipes and upon start up some being forced into the intake & cause white smoke! But no oil in pipes or inter cooler, but!!!! I found a 10mm split in the turbo vacuum pipe on the wastegate (hoping that’s the cause) let’s wait & see till tomorrow morning & the engines cold, please no more white smoke!!!!!

That's your problem. Very good! Might want to replace all the vacuum tubes and inspect the big pipes.