NHTSA Complaint #11615450 — 2017 FORD FUSION

I had the car about 3 months when the first service light appeared. Misfire - replaced the cylinder. But 2 months later service light came on again for same issue. Ford Dealership said it was coolant intrusion. Car repeatedly overheats. Service engine light comes on/stays on. Temperature gauge will indicate high temp, then will drop to normal seconds later, then shoot to the top again. At times engine will decrease power, and I have to pull over and park until engine cools, no matter where it happens. I don't feel safe driving on the highway, or any distance more than 20 miles or so. I am also afraid to park in the garage at night in case it's too hot. Ford dealership says it needs a new engine. Called Ford Customer Service but my VIN was not on the service action 19B37 or 21N12 (even though it was manufactured at a listed plant on the listed dates) so they would not assist in covering it.