When stuck in traffic or around town I suffer from power loss, almost as if it's gone into limp mode. No warning lights or messages, once the engine cools down it drives fine. If I have a decent run, i.e not much traffic it runs fine. I have also noticed a slight drop in mpg.
I've changed the Maf sensor, checked the turbo and intercooler and pipes, all are ok.
Any one got any ideas?