I bought my car 3 weeks ago and I opened the hood yesterday (while engine is warm) to see that the coolant reservoir is almost empty. Is it because all the coolant is in circulation or is the liquid over?

If I were to refill it, can I just buy the coolant and put it in the reservoir or do we need to add anything like water or sthg? I never tried this nor could I get information about this in faq or from the manual. Please let me know the instructions and cautions/precautions for filling in the coolant.

Thank you.

 

You add the coolant into the radiator while the car is running, not the overflow container. Mix 50/50 with water.