If you're not having much luck around Bribie, try Subi Evolution at Brendale.
I used to live at Sandstone Point and had a Twin Turbo Liberty. I had to do most non-logbook servicing myself because the mechanics in the area were too used to throwing Repco parts at KIA's.
Sorry for not replying before, I've only just changed my settings so I get notifications. My son's had a phone conversation with Subi Evolution and it was a helpful bloke he spoke to but no solution. We splashed out/wasted $249.00 on a Bosch OBD scanner which came up with no fault codes at all. It couldn't even read the O2 sensors.
I suppose the next step is to put in a genuine temp' sensor and see what happens. I'd like to take it down to Brendale, but with all the misfiring, it's got to be giving the cylinders a washing with neat petrol. Someone suggested head gasket, but it really doesn't seem like it to me. It's hard for a pensioner with a sick son though. He needs a car for when he gets back to work because you can bet your life the job offers come rolling in, in fact he's had three since he's been crook. Oh well, that's life.