I had a 1975 Jaguar XJ6, appropriately colored lemon yellow. If my memory serves me, it was carbureted with 2 Strombergs. This car had an orgasm almost every time I shut it off. The car would have a brief moment of silence after I shut it off, which would lull me into the false sense that it wasn't going to happen. Then it would begin, Za Za Za...... Za Za Za...... Za Za Za Za...... Za Za Za Za...... Za Za Za Za Za...... then a momentary silence, then BANG!, followed by a discharge of gray smoke from the engine compartment around the periphery of the hood (oops bonnet, sorry). It even happened to me on a blind date once. There was no living that one down.
There was a Jaguar Mechanic named Brian Morton who worked at the Jaguar factory in Coventry. He moved to the US and set up shop in Chelmsford Massachusetts. He was a wizard with these things. The Boston Jaguar dealer (located in Wellesley Massachusetts) used to bring the cars they couldn't fix up to Brian because Brian could fix them. I described the problem to Brain and he said "oh you have the fart bangs". He replaced one small condenser and voila, problem solved. When handed the small failed condenser and confronted with his bill I complained angrily, to which he replied "if you don't like it, drive a Chevy". I shut up and paid him and that was that. I ended up trading the car to an autobody shop in exchange for a paint job for my 1969 E Type roadster.