Why does my diesel Volkswagen Golf engine cut out and restart when I slow down?

I bought a brand new diesel Volkswagen Golf in January. There was a series of minor problems at first; tyres at the wrong pressure, pulling left, a burning smell next to the front passenger wheel arch, the motion sensor switch hanging out the wall and it using a lot of fuel. The thing that scared me most is the engine, while slowing down, cuts out and restarts itself. The garage can't find a fault and aren't happy that I've rejected the car. I have driven Golf models for a very long time and they've all driven well except this one.

Asked on 19 March 2017 by Caldwell

Answered by Honest John
I'd guess that you do a lot of repeated short runs from cold starts. Reducing the amount of NOx emitted by diesel engines increases the amount of soot they produce so the burning smell is the DPF actively regenerating and the poor fuel economy is due to the amount of diesel fuel it burns in order to regenerate. I think you should have bought a car with a petrol engine.
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