engine cuts out, injector light flashes?

hi can any one pls help,
iveco daily 65c 15 engine runs fine, but around 2,500 rpm cuts back to tick over red injector light flashes for about 10 seconds and then engine picks up again.
new regulator fited, new turbo fited, and new filters.changed deisle tank and feed pipe but still not sorteted.i all so have sort code,u o c f a but no one no what this relates to.many thanks