I have just replaced the cylinder head gasket on a Tigra 1.4. Since doing this the engine intermittently cuts out when stopping at junctions or stopping in traffic. This is not consistent sometimes it is fine and other times it seems to cut out all the time. Sometimes it is Ok at the start of a journey but then develops the fault after several or a dozen miles and other times it is the other way round. The other symptom is that the engine management light stays on for about a minute after starting and then goes out and remains out. Apart from that the engine starts with no problem, otherwise ticks over smoothly, has plenty of power and the new head gasket has cured the loss of coolant. I have cleaned out the idle valve control, but would have thought that it would have caused problems prior to swapping the head gasket anyway. Is there any obvious thing that could be causing this that I have overlooked, and is there any information anywhere about checking the fault codes without taking the car to a dealer (last resort)? Thanks in advance, Steve.