I have a vauxhall corsa club reg. 2007. The emission light kept coming on and then would go off, then car started stalling and generally not running well. My mechanic plugged it into the whatsit and said there was an error with my map sensor. This was duly replaced and although the car is now running smoother there is occasionally a smell of petrol. Is this connected to the map sensor? Being a woman i am, of course, totally baffled by the workings of an engine.