It does sound like a fuel thing. Even with no turbo surely it would be driveable? But just like limp mode?I had an (unmentionable non-VW POS) do something like this once because of a bad (but brand new) fuel filter. It idled a bit lumpy and had no power at all, and changing the filter fixed it. Doesn't the 99.5 have a lift pump in the tank? Maybe that died or blew a fuse?
someone suggested i check the timing. said that this is how a car runs when the timing is slightly off.any validity to that?