The 2g I just picked up has an odd bucking issue after start-up. I should mention first it has a completely dead battery.

After starting (jump start) it idles and revs fine sitting still, but if you try to put a load on it (I.E drive) it will buck wildly. When it does this the ABS light flashes on and you can hear what I assume is the MPI relay cycle. If you let the car run and warm up it stops completely.

It 'could' be that the battery finally holds enough charge to damp out maybe alternator issues, or maybe it's un-related. Anyone have any experience with this?

Is the MAF plugged in and no blown couplers on the intake before and after the turbo? If you have an aftermarket boost gauge. how much hg is it reading at idle?

I had an issue with this, the previous owner removed the recirc tube from the BOV to the intake and the car would buck once it got up to speed. I'd make sure that's connected and run a boost leak test.