Knocks Cold and Continues For 2-3 Minutes Increases W/Torque

^ Flywheel contacting splash shield. Reposition splash shield.
^ Loose or broken balancer or drive pulley. Tighten, or replace as necessary
^ Excessive piston to bore clearance. Replace piston.
Cold engine piston knock usually disappears when the cylinder is grounded out. Cold engine piston knock which disappears in 1.5 minutes should be considered acceptable.
^ Bent connecting rod.