We are missing a piece to the story because you do not need to remove the throttle body to do the water pump. I attached the process below.
The coolant coming out of the engine is most likely the pump is not sealing or was not installed properly which when hot would cause a lot of steam/smoke to come from the engine as well.
However, I would press them a little more on what the issue was when they removed the throttle body. At this point with high idle, I would suspect there is a vacuum leak.
Here are some guides that will help with this:
Let me know about this info and we can go from there. Thanks
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Monday, March 15th, 2021 AT 6:49 PM