[grahamdavis]

I have a S reg vauxhall astra envoy diesel turbo.
The orange engine managment light on dash appears often and i loose power(as if the turbo not working)
This happens when hot, cold, long & short journeys.

[MerseyPatrol]

you need to have diagnostic software plugged in and see if it has any fault codes stored. possible mass air flow sensor

[aylard]

My w reg Vectra had the same problem. It was the Mass Airflow Sensor. It's a little sensor in the air pipe near the engine. My garage charged me about £350 to have that part changed.