My wife was driving home tonight and had been driving for about 20 mins or so when the glowplug warning lamp started to flash. We think it was only flashing for about 10 seconds or so but on consulting the owners manual it says that flashing glowplug warning lamps are an indication of and engine management problem and we should seek to get the engine serviced soon. My wife was driving in too high a gear for her speed at the time and the light went off upon shifting down. Would that be a cause of the problem? We've only had the car serviced a few months ago. We don't fancy shelling out a few hundred for a service if it's unnecessary so if anyone can advise please do so Thanks!