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I bought my car 2001 x5 last 3 month. Last week during I drove back home it started weird sound from the engine and it stopped. I could not start it. Heat went up to the highest and there be stream. There was no coolant. Next day I put water and then my car could start. I took it to mechanic shop and checked for leaking. There was no any leaking. Then I drove back home during way back home it started heating again but now I stopped the car and checked. It lost some water.
How did it happen even there was no any leaking?
As the result from heating, how was my engine damage? How could I check my engine? It is still ok?
I check fan, it work and there was no leaking so what happen with my car??

I used to have some thing like this heat problem but engine never stop
On the way, heat went up then air condition stopped working by itself and heat went down. But after it’s dark nothing happen.

ur help would be greatly appreciated

replace radiator cap (which is not on the radiator), replace thermostat, and gasket, backflush radiator and block, and then the only other thing in the entire cooling system that is left is the waterpump.....but if you are running low on coolant, but no leaks, that points to a headgasket failure but it would smoke white...... about messing up the engine, if it turned off b/c it was overheating, chances are, you f-ed somethin up.... maybe warped the head, watch your gauges always, but if you want to check the engine for damage, do a compression test, and a leakdown test on it.......Hope this help