What Causes the Fluctuation of the Low-Pressure Gauge in a Car's Air Conditioning System?

[DeMaya]

Fluctuation of the low-pressure gauge indicates a significant amount of moisture in the pipeline. Additional information is as follows: 1. Car Pressure: The normal high-pressure range for a car's air conditioning system should be between 1.3 to 1.7 MPa; the low-pressure range should be between 0.1 to 0.25 MPa to be considered normal. 2. Testing the High and Low Pressure of a Car's Air Conditioning System: When the engine throttle is increased, the low pressure should decrease with the engine's RPM. The faster the RPM, the quicker the pressure drops, indicating good compressor performance. If the opposite occurs, it suggests a compressor malfunction. When the compressor is operating, maintain the engine speed between 1500 to 2000 RPM and activate the air conditioning to engage the compressor. Under normal conditions, the low-side pressure should be approximately 150 to 250 kPa, and the high-side pressure should be around 1400 to 1600 kPa.