Got the El's diagnosis done today to find out why the auto is slipping into limp home mode when it feels like it. Results: Nothing. No error codes what so ever on whole cpu. While I am not dissatisfied with a zero reading, the auto is still an issue. Its going in for an auto service at the end of next week ( earliest I could get it in), the mechanic said maybe it could be a plug that sits on top of the trans is burnt out and sending the auto into limp home mode? I think it just needs a service as the fluid is just starting to go a little browny colour and its prob breaking down at a low heat and offering no lubrication. I am worried though that no error codes were read, maybe it is the ecu becasue you would think a car that has got 320 thou on the clock and looks like it has not had the best life prior to my purchase would show some error codes. I know the inlet manifold gasket is shot, would this show as an error? Apart from a service what else do you guys think it could be?

disconnect batt, clean tps pins. Check oil level. reassemble see how that goes.

A fairly bad will send tranny in to limp mode and sometimes requires battery disconnect to reset.
But im suprised it didnt at least have a soft code

Just out of interest is your speedo working?
Have a look and see if your speedo sensor is still seated nice and snug in the tranny.
Could be stuffed or just not in properly?
My speedo sender was stuffed wasn't getting a speedo reading and this sent my auto into limp home mode. As far as i know many a thing can put your tranny into limp home mode. So good luck dude!