I have a 2003 Ford Fiesta Mk6 1.4 petrol.

A short while ago my engine management light came on. I took the car immediately to a local Ford dealer.

They told me it needed a new catalytic converter. I could not afford their prices at the time and so took the car away.

Two days later the engine management light went off and has stayed off. The car seems to be running fine.

I haven't replaced the catalytic converter.

Does this mean the catalytic converter is OK? Do they correct themselves or is it something more serious?