My 2007 Auris D4D 2 Litre was difficult to start during cold weather. Looks like the common problem for this is the SCV valve, which I replaced. I also replaced the fuel filter at the same time. Since then I have been having problems with the car going into limp mode and displaying a P0093 error. The car was running great before this (except the cold starting) with no errors. Any ideas what could be causing this problem?