METHOD AND DEVICE FOR COMPRESSION DIAGNOSIS OF AN INTERNAL COMBUSTION ENGINE.

摘要

A method and a device to determine the compression pressure in a combustion chamber of at least one cylinder in a combustion engine. The method comprises the steps : determining a first gas pressure in the combustion chamber when a piston in the cylinder is at its bottom dead centre; during a compression stroke in the cylinder, detecting a pressure change in the combustion chamber in relation to the first gas pressure, wherein the detection is carried out by detecting movements generated by said pressure change in a cylinder head belonging to said cylinder or in parts adjacent thereto in the engine; and based upon the first gas pressure and the detected pressure change, calculating the compression pressure.