What rocks smell like rotten eggs?
You're probably asking about Sulfur, an element commonly called as brimstone and is associated by some people to hell or the devil. The rotten egg smell is actually hydrogen sulfide (H2S) in its gas state.
If an automobile battery is in normal condition, there should be very little smell from it. The one smell that you should be aware of is the smell of rotten eggs, which indicates severe and dangerous problems with the battery. Once a battery begins to smell like rotten eggs, it cannot be saved, but must be immediately replaced. Please be aware that rotten-egg batteries can explode. Rotten-egg batteries are frequently much hotter than normal batteries…
A rotten egg smell is usually a sign of a failing catalytic convertor and also at times failing oxygen sensors. try the cat first and that should alleviate your smelly problem. answer before you change expensive catalictic converter, try using a different brand of fuel sometimes fuel company additives will make your exhaust smell like rotten eggs