Ecu problems???

Hi folks. Have a problem and looking for some advice. I have a disco 2 td5 which suddenly cut out on me and wouldn't fire up again. Was made aware of a problem with the ecu harness oiling up so I cleaned it out and got it going again. Went for a test drive and got about 3 miles when it suddenly cut out again and won't fire up. Should I still be thinking it's the wiring harness or is there somewhere else I should be looking? Any help would be greatly appreciated.

Worth a read (as is the rest of his site):
www.discovery2.co.uk / Workshop /Injector Harness

Have you tried a code reader? Could be something simple like a crank position sensor, but you need to check for fault codes.

Get codes read then report back.