A blown head gasket can cause a leak between the cylinder and the coolant passage, allowing coolant to enter the cylinder and reduce compression.
2. Damaged Piston Rings
Worn or broken piston rings can allow combustion gases to leak past the piston, reducing compression.
3. Bent or broken valves
If the valves in the engine are bent or broken, they will not be able to seal the combustion chamber properly, resulting in a loss of compression.
4. Worn or Scored Cylinder Walls
Excessive wear or scoring on the cylinder walls can allow combustion gases to leak past the piston rings, reducing compression.
5. Timing Belt or Chain is Off
If the timing belt or chain is off, the valves will not open and close at the correct time, resulting in a loss of compression.
