I have recently bought a 2.2 Prestigo Ulysse diesel and Ive notice that when its cold and I turn the ignition off and get out of the car I can hear a noise like I've left something on, Ive had a little look on my hands and knees in the dark and I think the noise is the fuel pump running and also sometimes a fan which is located under the passenger footwell. the noise normally continues for a couple of minutes after I turn the ignition off? A friend mentioned that it may be an Auxillary diesel powered heater, Ive looked in the handbook and found no mention of one, does anyone know if the Prestigo has one and what its for?