Very good..

I only mention FP reg b/c they are known fault on this chassis and I see many owners change all kinds of electronic controls [and spen hundreds of $$$$$$$$$] in vain, when the first place they should have checked was FP Reg....
If reg is allowing raw gas into engine through the vac hose. all the ECU controls are wasting there time trying to correct b/c they can't control a leaking FP reg. They try to, but they can't............same goes for a big vac leak...ECU mangaement only has so much electronic correction/adaptation percentage capability..
So, check these FIRST...they may/may not be the problem, but they cost Zero to check.