Hi Paul, I don't get and white fumes at all. Just a slight smell for about 5 seconds. However, looking at the service history and ownership, I find that my car was owned by Stratton for a month before being sold, and that owner had the car for two and a bit years when it was bought by Stratstone who kept the car for about 4 months, during which time it had a new engine under warranty by Jaguar [either an oil pump failure or wrong fuel]. It is a strong possibility that any modification need to rectify the auxiliary heater problem, could have been done then. Regards, Peter.