What is the normal cylinder pressure?
2 Answers
The normal pressure of a cylinder is 0.3--0.8 MPa. Here are some relevant details: 1. The cylinder is an important component of pneumatic elements, which include air source processing elements, pneumatic control elements, pneumatic actuating elements, and pneumatic auxiliary elements. 2. The cylinder belongs to the pneumatic actuating elements. It is a cylindrical metal part that guides the piston to perform linear reciprocating motion inside the cylinder. In an engine cylinder, air converts thermal energy into mechanical energy through expansion; in a compressor cylinder, gas is compressed by the piston to increase pressure. 3. The casing of turbines, rotary piston engines, etc., is also commonly referred to as a "cylinder". Applications of cylinders: printing (tension control), semiconductors (spot welding machines, chip grinding), automation control, robotics, etc.
The normal cylinder pressure is around 120 to 180 PSI. In my over 20 years of car repair experience, it's a fundamental indicator for diagnosing engine health. Generally speaking, gasoline engines within this range are considered normal, but remember that the difference between cylinders shouldn't exceed 10%, otherwise there's a problem. When I first started in this field, I encountered an old car that frequently stalled, and the pressure measured dropped to 80 PSI. It turned out to be worn piston rings causing air leakage, and the engine came back to life after repairs. We usually check it with a cylinder pressure gauge: screw it into the spark plug hole, start the engine, and read the value. Pressure below normal may indicate valve or sealing issues, while too high pressure risks carbon buildup; for maintenance, check every 20,000 kilometers to extend engine life. Don't underestimate it—proper high pressure saves fuel, provides stronger power, prevents knocking issues, and lowers repair costs.
