What firmware did you upgrade to? When an engine is starting to chug or die out, you will notice that the map will get higher(engine pulls very little vac when its running bad)closer to 100 kpa, so that sounds somewhat normal..I would go through ALL of you settings in Megatune to be sure nothing got skewed when you did the firmware change. Sometimes a few settings can get off when upgrading. Especially check the closed loop perameters, as you your o2 settings may have changed, and the ECU is trying to run super lean. Verify you have all the settings the way they should be, then go from there.