The CAT on my plus 4 still stinks with 47 k on the clock, but only after pushing hard or blasting up steep hills.. It’s a sulphur type smell and I often think that the stories of fumes from the exhaust are more related the cat.
Yes that's how to describe the smell - sulphur like. I guess it is the CAT then - does that mean it's faulty or leaky or is it just a "feature" or "factory specced optional extra"
I'm 99.9% certain it's not fuel. I had a Westfield (built by me) on the road for 20 years with a 1600 xflow in it - I'm familiar with the smell of fuel in the cockpit
On saloon cars, most cats are well hidden, so the smell is not so prominent, whereas on a Morgan it it is much closer to the driver with not a lot of barriers to restrict the flow of smell. However, if you google smelly cats, it is ONE of the signs of a failing cat. But, googling is a bit like looking up the medical dictionary when you have a pain in the belly!! You start to make a will right away.
As I said, under hard driving, mine did it from new and still does it 12 years later and has never had emission issues for an MOT. I guess if it starts to smell after a “normal”, gentle run, then it may need further investigation.
Sulphur Dioxide can be detected by the average person in concentrations of 1 p.p.m or less, and when you think of the mechanical joints on an exhaust system, it does not take much for minuscule amounts to creep out at joints.
