208 caught fire.

[Zuberismail]

Driving down to Henge with extended family, my niece, siblings and cousins were in a 208 2015 model. The car had coolant issues, but local mechanic seemed to have sorted it.

1 and 1/2 hrs on the M3, niece saw white smoke and a sign popped up to say pull over and park, she did, then saw black smoke. They exited the car and within seconds, it was engulfed within minutes.

They were extremely fortunate. No idea exactly what caused it.

[GiveMeABreak]

Hard to say but I'd certainly be talking to your local mechanic to see what he did.....

Glad everyone was ok

Catalytic converters can cause fire if they are over-worked due to excess pollutants.
Worn out water pumps or cooling fans not working can lead to overheating - but the Cat can get as high as 2000°C

[Zuberismail]

If they'd decide to drive a little further and stop, or had not been paying attention, the outcome could have been so different.

[xantia_v6]

If the car was not often driven at high speed, it could have been oil previously leaked onto the exhaust manifold which got hot enough to ignite it.
Those fires tend to flare up after the vehicle stops moving.

[Zuberismail]

That's what I'm leaning towards.

[Rp0thejester]

The main thing is everyone got out okay, a piece of metal on wheels can be replaced, a person can't

[Huskyxantia]

Id be asking questions to the chap whom was working on this car id want answers asap. Its good everyone is alive and got out. Some smug young grease monkey fitted a wrong fuse to my sisters car 8 years ago that caught fire her and my niece got out after seeing smoke coming through the heating vents 3p seconds later car gone , but they got out the way.

[Oldpug]

They way that car went up so quickly I would say there was a fuel leak? May be when working on the car that mechanic dislodged something?
What ever, your family are safe that is the important thing. Just hand it over to your insurer, they may get an expert to inspect the car, but by the look of it I doubt the cause of the fire will be identified.