C3 picasso 2015 1.6 diesel (cranking not starting) just after a major service

[CitroJim]

That sounds like all the fuel is not being burnt when the engine is cold. I don't know enough about that particular engine but it suggests to me you may have faulty glow plugs.

That's my thought too. HDi engines do not need good working glowplugs for initial start, unless it's very cold, but they do come into operation as soon as the engine starts and remain on until the coolant temperature reaches a set level. This is known as post-heating and is essential to control emissions and smoke..

It may be worth a diagnostics session as any faults in the glowplug system may be revealed.

Excess urea (AdBlue) injection will cause whiteish steam and this can easily be diagnosed by nose... The exhaust will smell of ammonia if this is the case.

[Jeff2021]

Hi there, thanks guys for all your inputs, big help for 1st time diesel car owner like myself. Yes the car has an adblue system as it says to its manual. Also just to add some info, the appearance of a thick smoke doesn’t happen all the time, like today climate is at 7*c, it starts well without any visible smoke. I observe only during cold starts when it’s around 0-3*c outside here in England.

[Jeff2021]

Yes PaulC5 the car has adblue according to its manual. Im planning to have it checked by a mechanic sometime next week

[Stewart(oily)]

When I did the cambelt on my 2010 C3 HDI I was crestfallen when it did not burst into life at the first turn of the key, I have replaced many cambelts and I am somewhat obsessive about correct procedures so I expect them to work properly, it turns out that the crankshaft sensor was damaged during removal/refitting, it was working electronically but was very slightly out of place ,it locates with one bolt and a plastic dowel, th dowel had corroded onto its pin and broken away from the sensor, another sensor and voila! very hard to spot.