Thanks Hayden,
I did a couple of things on the weekend, cleaned the Mass Airflow sensor, which was really dirty, then pulled out the fuel pump (big job just for checking the filter!) Neither seemed the issue, as it still played up after looking at those.
However, your third idea of bad fuel may well be the issue.
Thing is, there has been no engine light. I do have an OBD2 reader, but for some reason I can't get readings with it on this 2001 Tarago - yet I can on my 2006 Estima.
Anyway, I let it run for about 10 mins and after that long warm up it seemed better - I could actually get out of the driveway (a medium incline), So I took it for a long hard run, topped it up with 98 fuel and added some Valvoline injector cleaner (seems there's a split camp as to whether that does anything - I wouldn't have a clue).
Since then, it seems to be heaps better, almost the best it's ever been. So... maybe you were right with the fuel quality. Hopefully it was just a bad batch of fuel. Time will tell.
Thanks for the ideas!
P.S. Looking at VCI, nice!
Cheers,
Brett