[turbothrush]

Do you mean you installed the new parts and there was no change at all ?

Did unplugging the new OEM o2 sensor make any difference ? As Ryland suggested in your other thread.

When you say fluttering idle do you mean hunting up and down or do you mean missing as in a non firing cylinder?

The vx hardly ever activates egr so I would not spend much time on it until you get the rest sorted out. Just make sure it is not stuck in the open position. Stuck closed is ok at this point

Like most cars the vx has quite range in mpg. Summer vs winter.long trips vs short trips. 35 mpg in the winter. Yep I have got that before. See my fuel log if you want