Cylinder pressure testing hole structure for large-power diesel engine cylinder cap

The invention provides a cylinder pressure testing hole structure for a large-power diesel engine cylinder cap. A cylinder pressure testing hole consists of a pressure testing channel, a sensor installation threaded hole and a sensor installation counter bore in a cylinder cap, wherein the pressure testing channel, the sensor installation threaded hole and the sensor installation counter bore in a cylinder cap are set sequentially. The axis of the pressure testing channel, the axis of the sensor installation threaded hole and the axis of the sensor installation counter hole are located on the same central line. One end, close to the pressure testing channel, of the sensor installation threaded hole is provided with a sensor tail end volume chamber. The structure has the following advantages that the pressure testing channel is perpendicular to the bottom plane of a sensor, and the structure can reduce the pressure oscillation; the structure reduces the length of the pressure testing channel, reduces the volum