Erratic idle, misfiring, oil pressure light

[madinnit1974]

Hi I am a newbie to the site but am in desperate need for help. I have a 1999 Seat Cordoba 1.6 petrol I have been having problems with the car overheating and now the car wont idle without cutting out and seems to be misfiring, I changed the plugs and leads and still the same, so I changed the coolant temp sensor to see if this would help and it still the same only now the oil pressure light is flashing and beeping, so I am stuck for things to try. I was wondering if anyone could give me an idea of what it could be.

cheers Martin