Ok so I recently replaced my head gasket with a .4mm cosmetic head gasket and replaced the spark plugs because my belt snapped downtown and I had to drive it home without a belt and when I went to turn it on for the first time after the replacement I got a cylinder 4 misfire code and after revving it a little I got a idle higher than expected code and I can’t seem to figure out why. I am running 17% pulley with forged internals can anyone help me diagnose this please

 

Post codes. Also have you done a leak down or compression test?

might also do a smoke test for vacuum leaks