Hi again

The FAQ "hot no start" is great. I've had 4 starting problems in the past and all of them were as described in the FAQ. The recent one was involving the radio supression relay which replacing it was a headache but that is a another story.

I do not wish to be stranded again and going by the FAQ I've had to replace 4 of the items mentioned so far. Going through the list there are 5 more components which to my knowledge are still original ie

Engine Coolant Temp sensor
Fuel regulator
Fuel pump
Gas cap
IAC (in my case auxillary air valve)

My car has around 250k km and nearly 16 years old and with the components failing one by one should I replace all the above as preventative maintenance?
How long do these components last though? And can they just fail without warning?

Thanks