What happens if I drive without antifreeze in my car (no water / no antifreeze)? This is my main question. I've added some follow up questions that are specific to my situation but for the main question I just want to know in general what happens.
Let's say someone thought that the low antifreeze light was the low windshield washer light and drove a 12 mile trip to work and home from work in the middle of winter for a month? What happens if they drive in the summer?
For the record, for me, I realize now that I was driving with low antifreeze except for maybe one or two trips (of about 40). I believe a few trips I ran completely out because the temperature shot up 10 to 20 degrees over the span of a mile. I pulled over as soon as I noticed this and could pull off the road or into a gas station and added coolant.
I was able to take it in to get fixed. The mechanics ran pressure tests on it and found the coolant leak in the water pump. They replaced it and it's running fine since then. However, the engine seems to knock / rock very loudly sometimes at start but eventually dies down but that may have already been happening. I don't know. Anyway, no leaks.
I took it to one shop and I said that I had a radiator leak. They ran pressure tests and said the radiator and water pump were leaking. I took it to a second shop and they said that only the water pump was leaking. Is the first shop's pressure tester unreliable?