Failure with the cold engine

Hello, I have a Peugeot 306 90 CV TD, which has a few days failing in cold,
I spliced, I let the light of the heaters be extinguished and start perfectly but the engine heads and made white smoke, when the engine is hot no longer does, the air and gas filter are new, verified heater are fine, that it can fail.
thank you

Can you have an injector failure, I made a diagnosis to see what error code shows you?

Hello, this Peugeot 306 TD 90 CV car is from 1998, it is PSA engine, it has no center to make diagnosis,
today I have changed the gassoil filter again, it seems that the failure does less but it does, and it also does it hot, I do not know if to remove the injectors and take them to check them That I have solved it can make me a hand.
thank you

What injection pump class does?

Place the complete car data, the more information the help will be