Navara zd30 with Problems

I see through a web search that there have been engine and g/box probs with these an patrols on this forum. My father-in-law recently bought one (navara dual cab zd30 2002 I think) and has had heaps of problems with it cutting out on him while driving.

After doing so it will re-start after the key is turned off. It will not re-start if the key is not truned all the way off. Once it re-starts, the engine will not idle correctly...often as high as 1600rpm. He has had it to the local nissan agent who put the compter on it while faulting. The diagnostics showed everything ok??? They have serviced the EGR and now have no more answers. It's off to Nissan in Brisy next week.

Is this something common or just an oddball left fielder with this truck?

Your thoughts?
Theron