Thanks alot guys, yes I've cleaned it up and I'm just doing jobs on it here and there. Recently done the timing belt and water pump which was the main engine job that it needed. Then it's just keeping it on the road 🙂
If you,ve replaced the cat with a cheap aftermarket one, this will often throw a code relating to the O2 sensors.
Unfortunately only real way to deal with it is a proper oem cat...expensive I know