Hello, is your first statement saying you ran the engine for 3000 miles with the management light on and then the engine died?
AFTER REPAIR OF ECU THE CAR COVERED 3,000 MILES BEFORE LIGHT CAME ON AND WENT ON TO GO IN SAFE MODE ETC .
Can you also confirm the year and engine details. Vauxhall didn't do the 1.9 diesel in 2000 or 2002. Can you check the engine code.