How to Measure Engine Cylinder Pressure?

[DiJanelle]

Detecting the cylinder pressure of an engine can be done as follows: 1. Use compressed air to clean the dirt around the spark plugs, then remove all spark plugs. For gasoline engines, also disconnect the secondary high-voltage wires of the ignition system and securely ground them to prevent electric shock or fire. 2. Insert the conical rubber head of the dedicated cylinder pressure gauge into the spark plug hole of the cylinder being measured, ensuring it is properly aligned and tightly secured. 3. Fully open the throttle (and the choke if equipped), and use the starter to rotate the crankshaft for 3 to 5 seconds (no fewer than 4 compression strokes). Stop rotating once the pressure gauge needle indicates and maintains the maximum pressure reading. 4. Remove the pressure gauge, record the reading, press the one-way valve to reset the gauge needle to zero, and repeat this process for each cylinder. Measure each cylinder at least twice, take the arithmetic average of the results, compare them with the standard values, analyze the results, and assess the working condition of the cylinders.