问：汽车曲柄但不会启动。

Sons car will turn over but not start a lot of the time. It was dumping some water going uphill and seems to be hot but gauge is broken/no steam. Losing water and have to replace but no noticeable leaks but overflow dumps after climbing up hill. After driving it it may not start again for the rest of the day. Used to be till cool 2-4 hrs but now all day if not till next morning. He runs battery down sometimes trying to start it. Positive battery cable was very corroded. Cleaned it thoroughly and next day was corroded again. Looks like something leaks out of it because of streaks running down side of battery but not on top. Changed dist cap & rotor. No help. Put in new thermostat today. Ignition lock switch spins. Not symptoms of relay, seems to be getting fuel but no spark. Ignition coil is my best guess but would LOVE some other opinions/possibilities PLEASE. Tonight he couldn't get it to start. I tapped on the coil and then pumped it a few times and it started right up on 2nd try.

我的汽车有165000英里。
我的汽车有自动变速箱。