Won't Idle

[Grub54891]

Lets try a different compression tester just to verify the readings are correct.

 

[skippy2235]

To be fair, it would have to jump lots of teeth to get 30 psi in 3 cylinders.
Also check for water in the oil, and compression in water.
Cause blowing a head gasket on 3 cylinders is not easy.
My guess is a cracked head or block during winter.
But 3 cylinders is not usual.
but not impossiable.