The antifreeze will not stay in reservoir, and the engine is racing too high.
The coolant reservoir will need to be checked to see if it is leaking or if the engine has an overheating problem. The high idle may be due to a vacuum leak at a hose or a faulty throttle body idle control valve. I recommend having a certified mechanic locate the coolant leaks and inspect the engine’s high idle in person. They will be able to make a full diagnosis and repair for both problems to ensure that your car is safe to drive.
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