My mother-in-law who is not the most mechanically sympathetic person I know (and therefore the most unlucky.....) arrived in Manchester this weekend (as she does every few weeks) in her 2009 Kia Sedona. It has the latest 2.2 litre diesel engine from the Hyundai Group. She does a fairly high mileage, with a good proportion on motorways. She announced that the engine management light was coming on every so often and the dealers with whom the car has always been serviced have advised it needs a £400 job - doing what I am not sure but she muttered something about valves??

So firstly, any ideas what the job might be? I suspect it might be something to do with poor quaity fuel and I advised her to start using Shell Nitro+ before she spent that money. Good advice??