I have a 2010 Prius with 206K miles on it, I’ve only owned it 8 months but have read about the issues these things are notorious for. As of yesterday it started cold start knocking hut went away after about 15 seconds logging code of misfire cyl 4. This morning it started no issues but once I started driving it began misfiring, bucking, and knocking again. This time for cyl 2 misfire. I replaced injectors a month ago, No coolant loss or excessive oil consumption, I’ve cleaned the EGR cooler until the point I could see through it with a flashlight, tested and cleaned EGR valve, swapped coil pack from 2 to 4, plug from 2 to 3, and injector from 2 to 1, started it back up and knocking right away. I removed and cleaned the intake manifold or carbon buildup and oil, I checked the EGR valve again for it sticking but it moves freely but it’s still knocking/misfiring for cyl 2. It will start up fine for a few seconds and go right into the misfire. Any help would be greatly appreciated. iPhone ?
With that many miles, get a leak down test of the head gasket. If it’s blown, anything you throw at it won’t permanently fix the issue.
