I have a Vauxhall Astra 2.0 DTI estate 2001 with 52000 miles on the clock. When on the motorway in 4th or 5th gear and the revs hit 3000RMP the ecu light comes on and there is an immediate loss of power. The light stays on until the engine is restarted, the power and the light then come back up. Could anyone throw a little light on the subject please. Many thanks.