Engine Trouble NEED HELP FAST PLZ

My '91 Model Ford Courier 2.6efi also known to some as a Mazda b-series 2600 has been having trouble for about 4 months now. The engine runs fine for a while then out of no where will cut out. ive found normally when alittle warm. ive replaced fuel pump, relay and also filter. tryed a second hand dizzy still no success. i also have to replace the cat-con it started to get very hot and bits of hot metal came out the exhuast but this was after the problem about a month. if anyone can give me any advise or maybe if anyone has seen things like this before it would be a real help. my car missed rego and now i have got to get a Blue slip for it. in addition a mate of mine placed gauges on the fuel line it was around the 300 mark

Thank you to anyone that can help in anyway