S4, Tamora, Conti GT
On my drive home from Bristol yesterday, noticed a funny eggy type smell a few times which would only last a few minutes. Then realised that there is a nasty rattle from under the car. Put the car on the ramps heat shield all seems tight but when I bang the cat it rattles, does this mean it's shot? Is there anyway of repairing these? Car passed its mot last week, I'm not paying 300 for a new cat, is a decat pipe the best option. Also I have a yozza catback on my 182 will any decat pipe fit?