Cylinder 1 Misfire and overheating- 2010 Toyota Corolla Model S- 155k miles
So about a month ago I was in my car on my lunch break from work and the check engine, VSC off and traction lights all came on. I popped the hood to see if there was anything obviously wrong and the coolant was basically empty. I went to autozone and got more coolant and had them run the code on their reader and it came up as a P0301 (Cylinder 1 Misfire). The employee suggested it might be the spark plugs so the next day I changed them myself. The lights went off and I assumed everything was fine. After about 3-4 days the lights came back on again and I decided I needed to take it in to a mechanic. I had to wait a few days before I could get it to the shop so I just kept my eye on it and after 2 days I was driving home and it started overheating. I pulled off and popped the hood and the coolant was empty again. I refilled it and brought it to the mechanic soon after. The first time I brought it in we changed the coils and replaced the radiator cap, I got it back and the next day the lights came back on. I brought it back and he looked over it and said that when I had replaced the spark plugs I didn’t tighten them enough so they were causing the engine to run too hot and push the coolant out. I got it back and the next day the lights came back on again and when I tried to drive the car started overheating. I had just driven about an hour and 15 minutes. I pulled off and had it towed back to the shop. This time my uncle who is a mechanic (he lives in another state so couldn’t help) suggested changing the thermostat. We changed the thermostat. I got it back and about 2 days later the lights came back on. This is where I am now. He called two days ago and said that he switched the plugs and coils in cylinder 1 and cylinder 4 with each other to see if the misfire moves to 4. After he did this he drove it around almost 100 miles in the last few days and hasn’t been able to get the misfire lights to come on but it is still overheating after a long drive. He suggests that it might be a clogged radiator and we might want to just replace it. I really don’t know what I should do at this point. Is there anything else it might be that we should look into? Is it even worth it?