Suspect the ECU is faulty causing hard starting. When finaally sstarting puffs big smoke untill clear. Otherwise runs beautifully.

I suspect your car doesn't have a choke if it is EFI.

I'd suspect a faulty coolant temp sensor unit, which is not telling the ECU that the engine is cold.

Some EFI cars have an extra injector called a cold start injector. If fitted this could be faulty.

In both the above cases there may be an ECU trouble code you can read out. In the US Autozone will do this for you.

In the old days the classic cause of hard starting was always faulty engine timing. If your car has a timing belt and it is worn, it may have jumped a tooth or 2., but this is uncommon.

black smoke is over fueling and although the turbo appears to spin ok the vale variation actuator may not be operating correctly
there are vanes in the exhaust turbine housing that are altered to increase the exhaust gas flow onto the turbine blades for quicker acceleration and these vanes are operated by a vacuum actuator and rod by a sensor
the vanes are subject to extreme heat and can rust stuck open or the hose gets hard and cracks
s not allowing the vanes to work
I would be concentrating in this area before the EGR valve
run the fault codes as well to get a better idea of the possible fault as some systems only put the light on for extreme conditions in engine and transmission

if it is an EFI controlled vehicle then run the fault codes to find the faulty area ( could be faulty injectors or low fuel pressure to the injectors)
If it has a carby, I suspect that there is a float problem or the choke is staying on
black smoke indicates over fueling or lack of fuel control

What size motor? Older engines will start to have valve guide wear and this can cause a small amount of oil to seep into the cylinder after the engine shuts off. This will cause a small puff of smoke on start-up. If the smoke clears up immediately, there is really no major problem. Be advised that on the GM motors, it is the back two cylinders on the v-6 and v-8 engines that this usually occurs. As the condition worsens with age, the oil can cause plug fouling resulting is misfiring. Changing or cleaning the affected plugs will remedy the issue for a while.

Black smoke is too much fuel. My guess would be that there is an injector that is stuck open draining the pressurized fuel into a cylinder or several cylinders. And that is a considerable amount of fuel. And it would account for the hard start because there isn't any fuel being pumped into the other injectors until the pump builds the pressure back up.

It sounds like it has jumped time. What year is the car and how many miles. Timing chains can go bad as early as 70,000 miles

Sorry but white smoke is a sign of water getting into 1 or more cylinders.I would pull the oil dipstick and see if it looks like a creamy color.If it does then you may have a blown head gasket or a crack in the engine block somewhere.

It's your valve seals... You start it get a big puff of white blue smoke than it goes away? ^^ idiots

Suspect the glow plugs or timer not working proper. You could plug your truck in keep the engine warm so it starts easier. Or you could have the glow plugs tested and replaced if faulty. Your engine has 8 glowplugs and even a couple faulty glowplugs will cause problems starting. You could have injector or injection pump problems as well but harder to diagnos yourself.

Sounds like the smoke might be unburnt fuel and the fuel injection(ecu) needs to be plugged into a lap top while vehicle on dyno and set up the fuel curves etc to the engine requirements.You have changed too much.Your original air flow meter will no longer be sending the correct signal due to your intake mods being way outside the way it was supposed to run and your airflow speeds have changed there by changing the signal the ecu gets.Good luck