EPC light has come on

Hello, I own a vw polo twist 1.4 hatchback. It's a 54 plate and I've had the car 2 years. Since I bought it I have had quite a lot of problems and I've already spent more money than I can afford on it. A month after I bought it the engine management light came on and has stayed on pretty much since then. On diagnosis it showed a catalytic converter error code. The mechanic cleared it and advised I go on a long journey as it may be due to the car not getting long enough runs. I did this and 2 years later I'm still with the same engine light. Earlier this year I was driving at 40mph and the car began to lose power and the speed was dropping dramatically. The engine light and EPC light both lit up so I pulled over and stopped the engine. After 3 mins I restarted the car no problem. Just to be on the safe side I called the AA and they diagnosed the same fault as a year and a half previously (catalytic converter). He said it might be I need a new coil but as it was running ok again he said I should wait and see if anything happens. Obviously I would much rather it be a coil problem than me needing a new cat so I was more reassured after this. Since then I haven't broken down but engine management light is still on and the car occasionally revs on its own accord when I'm stationary. I am worried because of an upcoming 400 mile round journey and if it is the catalytic converter am I at risk of inducing the problem by driving it for such a long time? I'm so worried about it I'm considering selling the car and buying another one before I go on this long trip! Please help with any knowledge or advice that you know! Thank you

Thank you for your reply. If the catalytic converter does 'melt down' will that mean a non starting car and a new cat? Thank you

Hi there. No I haven't rectified it yet. I had the AA out to see it last week and now the diagnostics are showing an EGR valve fault plus another fault which is catalyst efficiency below threshold. So apparently its all due to the EGR valve and not a coil as I thought. AA man tapped the valve with a hammer and advised me it may just be clogged up. The engine management light hasn't come back on as yet but knowing my luck it probably will. When it does I assume I'll have to spend more money on a new EGR valve and hope for the best!