bad gas. quick question..how much dry gas?

[benhogan]

i filled up my e320 with the usual premium. the car started idling funny and had gutless acceleration the next day.

i did not have any drygas so i stopped by the closest Dollar General and got STP fuel treatment which I assume is the same stuff plus 'additives'.

question- how much drygas can i put in? i want to get the proper drygas this morning and really drug it up as much as i can. Would overdosing it be harmful? doesn't that stuff just bond with the water or something? does it make the water evaporate or does it make it combustible?

what about 100% isoprophyl alcohol from the drugstore? same stuff right? but how much do i put in.

I don't want to kill the car. I just got it!