Originally Posted by 80stech

It would probably be a good idea to have a look at the plugs and coils if that hasn't been done in a while. Good to do the fuel pressure test too even if that's not a problem so that you get familiar with how that works. I have a had a similar issue with mine when after sitting for about three days but then it acts like it's flooded. I suspected the injectors leaking but when I pulled the rail nothing was obvious so I sent them out for cleaning and testing but they could only just clean up the ends a bit because they said I have the Siemens injectors which have ceramic seats and will be ruined with ultrasonic cleaning. They flow tested and all was good but they did say all the injectors leaked just a tiny bit. I suspect that 2 or three days was just the right amount to vapour flood the engine anything less was not enough and longer would have given the vapour time to dissipate. Anyway it's very rare that I let the vehicle sit for 2 or 3 days anyway and knowing what the problem is makes it not worth replacing the injectors for.
Whatever the issue though it's always good to have the plugs and coils in good shape.