Hello and Welcome -
My name is ***** ***** Im happy to help / advise.
For this to be happening, the cooling system is failing at some part -
Things to check :
Check the cooling system cap is fitted - not missing or loose.
Water / coolant level - in case of unseen loss.. top up and re test .
Fan - cooling fan operation.
I note too you said the engine lost 90% of its power.. This could be serious - you will first need to check as above.
If the water / coolant has been lost - top it up and retry ... if it will. If you still have engine troubles, you will need to remove the engine spark plugs ( petrol ) glow plugs ( diesel)... and spin the engine.. see if water comes out of the holes ... if so , then Im afraid you have a failed head gasket likely as not and that would then need deeper investigation.
Quite why any of these things happen "just like that" is hard to say, but they do.. so you need to work through as above on this one to make progress.
Let me know how you go..and / or let me know if you need anything further on this.. I will be back on later today if you need me -
~>>~~>>~ Meanwhile now at this point- Please do click on the "Exc / Ok rating" for me at this time.. "Thank you" in advance for that .
.. Note that you can get back to me anytime at all after doing the rating - it doesn't close you out --
Best Rgds, MIKE