Run Away....FAST! Thats my best advice
My experience with a friends 92 3.0v6 has been nothing but grief... as I ended up being the problem solver after several mechanics threw in the towel! Lessons I have learned from the sorting:
The V6 runs very hot in a confined engine bay (you need to let it stand for over 1/2 hour after a test lap to work under the bonnet!) and it tends to lead to warping & cracking of the heads.
It is a very sophisticated (read complex) ignition & Control system with many parts in the loop to diagnose if it start acting up. Lots of fun when you are out bush!
There are several known components that go bad (mainly due to heat) such as the 'power amplifier' that boosts the signal to the coil (only $40 to replace... I have swaped it out 3 times already), the crank angle sensor in the distributor, and the capacitors in the ECU itself (very common). Also burnt out exhaust valves (especially on the rear cylinders) seems to be all too common (his engine has done this).
My friends engine has been rebuilt twice (once at 80K and again at 230K... new heads etc) and has been well maintained. It started playing up again (randomly dying and staying dead for 30min at a time) about 6 months ago. That is when everyone else threw in the towel (after much $$$ of course!). We replaced all the plugs/leads & new dist. cap (ran smoother higher up the rev range but still not great), I rebuilt the ECU with new low esr computer capacitors (regained proper idle control and fuel economy), replaced the power amplifier which helped a bit, and also replaced the loom going to the cranks angle sensor (old one was a bit brittle with snapped strands in the wire). It ran really good after all of that... right up until it died for no reason when hot!
So we saved the most expensive until last... and replaced the crank angle sensor ($300) and all was well with the world with the Paj finally being a proper car once more!
Don't get me wrong, off road (especially on sand) it was a really good vehicle with all that power... and the driving position & handling were almost car like. However with so many ongoing gremlins the remote travel reliability was always in question. It has since been replaced with a 2.8L D Hilux!
Whilst this is only my experience with one vehicle... searching for solutions I discovered so many mechanics that no longer touch them (lost time, no result, too many issues) and also just how many other owners had the same hassles! Basically a great car but made overly complex for its intended duty. The diesel varient doesn't seem to suffer any of these traits however!
Hope this has given you an idea of what to look for if nothing else!
Cheers Harvey