Dedra turbo poor idle and high HC emission

[Raz]

Dedra Turbo idles very badly and just failed MOT on HC emissions (were 1700 - pass is 1200).

Runs fine except on idle.

The exhaust is a bit hazy - greyish white fumes when it's warmed up.

Also it stalls easily (the MOT tester stalled it many times during the test) and it filled the place with its haze when he revved it hard to get it onto the ramp.

Any clues?

[Tiff]

Sounds like the coolant temp sensor is away,try unplugging it with warm engine,and see if it stabilises
Otherwise could be the throttle switch on the inlet manifold,this can cause similar symptoms.Try these two first and see how it goes.