The subject line just about says it all.

When it first happened a couple of days ago, it would only cut out under boost pressure. The engine would momentarily die for a fraction of a second, and then it would catch and keep accelerating.

Now it's happening regularly, and even during acceleration when no boost presure is present. It idles perfectly, and does not actually stall (just cuts out for a fraction of a second, and catches again).

The problem coincides with a new tank of gas, so I'm wondering if I picked up bad gas. But I bet it's not that simple.

It's pretty much undriveable now, although it was an erratic problem at first.

Any helpful diagnoses? Thanks!