I’ve had smelling rotten egg smell when I get on it for some time now. But I’ve never a the temp huge go up a if it was overheating. When I purchased the car about 6 years back one of the cats upstream the whole top separated. I had to remove the entire exhaust and weld it back all the way around the circle .put it back in but I have no idea what this car has been through with the previous owner or how long it had been driven like that