Mazda RX-7 started off seeming hard to start as the clutch needs to be pushed in to start. Almost to the point of pushing it in so much, my leg hurt. It would start, but lately, just barely. Then it started to overheat. So I filled it with antifreeze & tried it again. After a couple of minutes, it was blowing cold air again, so I drove it 5 km & steam started coming from under the hood especially when I stopped the car. I let it cool down & went to get antifreeze & also radiator leak sealant at Canadian Tire. I started the car, but it was hard to start & ran rough. 30 secs later, I was able to rev it up. I hardly made it across a main intersection. I ten pulled over & then it stalled. I noticed my signal lights or tail lights didn’t work but my headlights worked (just barely).

I will do a load test on the battery & see what that says. Maybe that’s all it is.

 

I'd check compression and also find out where the water went. Was it a bad hose/rad/exit exhaust as steam, etc...

 

Have a look at you ast. It might have a split

 

Can't give you advice without knowing the series of car that you have.