What are the causes of insufficient cylinder pressure?

[DeFrank]

Causes of insufficient cylinder pressure include: 1. Wear of pistons, piston rings, and cylinder linings resulting in excessive clearance; 2. Damage or burning of cylinder gaskets, or loose cylinder head bolts; 3. Poor sealing between valves and seats, insufficient valve clearance, broken or weak valve springs, or stuck valves; 4. Deformation of cylinder heads or blocks leading to poor sealing; 5. Incorrect valve timing. A cylinder is a cylindrical chamber within an engine where a piston is driven by the pressure or expansion force of the working fluid. Some special engines may have non-cylindrical chambers. Common cylinder counts in automotive engines are 3, 4, 5, 6, 8, 10, and 12. With the same bore diameter, more cylinders mean greater displacement and higher power output. For the same displacement, more cylinders allow for smaller bore diameters, enabling higher engine speeds and greater power enhancement.