Hi all, new to this so apologies if I get it wrong. I have an 06 xc90 D5, that on the whole runs very well. However when I accelerate to around 4K rpm to overtake for example, my engine system service light comes on. I have no loss of power and the car still runs fine. The light for some reason goes off after about 2 days and stays off until I 'forget' and do it again. (3 times this year!) my garage read a boost pressure fault, an atmospheric pressure fault and an injector fault on old codes but have no idea what is wrong. They just say it runs fine so ignore. It. I've changed my map sensor 2 months ago but it did the same thing again today. I really don't know where to go with this it's driving me insane especially cause it still runs very well. Appreciate I could go to a Volvo specialist but I'm not ready to handle a large bill just yet. Any of you out there that have had any similar experience from this I would really appreciate some gen. thanks all