The engine compression test is a method by which accurate information about the condition of the engine is determined. By measuring compression pressures, it is possible to detect leaks in the combustion chamber of individual cylinders.

Leaks in the combustion chamber adversely affect the entire operation of the engine, its performance, fuel consumption, engine oil consumption, the number of emissions produced, and more.

The compression ratio is one of the basic characteristics of a piston combustion engine, which indicates the cylinder volume ratio between the piston in the bottom and the piston in the top dead center.

The compression ratio is thus the ratio of the entire working volume of the cylinder to the volume of the compression space. In other words, the ratio between the volume of the mixture sucked into the cylinder and the volume of the mixture compressed in the cylinder.