'08 head gasket?

Clean up the plug Wells first get all the moisture and everything you can cleaned up and see if the misfiring stops. Then check your plugs maybe resistance check them or replace with new and resistance check the new ones to make sure you have the right K ohms.

 

P2601 is set when the ECM "sees" something is wrong with the Coolant Heat Storage tank water pump or relay. Short term - ignore this code until you have nothing better to do (or if you need the check engine light to stay off for inspection).

P0301/302 - lots of things can cause misfires.

First check that all fluids (oil, coolant - in the radiator, etc) are full.

Replace the spark plugs with NGK or Denso from a reputable source (ebay and amazon are known to have counterfeits). Consider replacing the ignition coils - again Denso or Toyota from reputable source.

Any moisture in the plug bores can cause misfire. The hood - cowl seal leaks onto the engine and can cause your problems.

The early symptoms of a head gasket are misfire on cold start-up that lasts a few seconds along with slow coolant loss.

Head gasket problems are extremely rare on Gen2 1.5L engines.

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So your wiper tray is in right and your wipers are installed moisture if it gets on top of the valve cover sometimes it can seep through and be riding in that ridge between the spark plug extension and the actual valve cover itself there's a little ridge there and water can sit there when that overfills it'll run down the sides of the extension and sit right down against the spark plug and will cause a misfire and it will be random because it could be a couple cylinders that have just enough moisture to cause a miss but yet don't really wipe out a lot with the towel or something I just use something like moisture remover wire dryer spray whatever and leave the plugs in the coils out for a few minutes while I'm doing other things let everything dry up but water should not be getting in there from the engine there's no water jacket anywhere near the spark plugs so it's generally got to be coming through the seals around the coils usually during the rain or heavy car washing or I don't know what I see more of this in the generation 3 that thing will pick up moisture from zero moisture air it's unbelievable.