Why is my AC not engaging?

If the compressor clutch doesn’t engage; that usually means there’s an electrical or mechanical problem with the compressor. Even if you just filled up the AC system with refrigerant, if the AC compressor can’t operate correctly you’ll get warm air.

What happens when I Turn on the a / C?

The compressor does engage when I turn the A/C on, I can hear some noise through the evaporator, and the low side pressure drops. The high side pressure will only increase by about 2 psi, barely enough to move the gauge. Here is exactly what I get: Also no changes when the engine speed is increased.

Why does high side pressure not change when compressor is running?

Basic summary is that the low side pressure drops, but the high side pressure doesn’t change when the compressor is running, so I suspect blockage upstream of the compressor. Okay – got all the stuff, so I guess we’ll see how it goes. I’m not an AC guy, please let us know how it goes.

How does high side pressure affect engine speed?

The high side pressure will only increase by about 2 psi, barely enough to move the gauge. Here is exactly what I get: Also no changes when the engine speed is increased. The compressor runs continuously as long as the A/C button is engaged. I believe there is plenty of refrigerant in the system based on the manifold gauge readings.

What are the symptoms of a bad AC pressure switch?

The most common symptom of a bad AC pressure switch are that you will notice that the AC compressor is cutting on and off rapidly when you are idling your car. These switches between on and off can be noticeable on the engine’s rpm, and you may see or feel fluctuations from it.

What should my AC low side pressure be?

When the engine is on and the AC is on high, low pressure readings should be around 30 psi and the high pressure side should be about 250 psi depending on your car. The correct reading will display once the clutch engages and the gauge stops cycling.

What should the AC pressure be when the engine is on?

When the engine is on When the engine is on and the AC is on high, low pressure readings should be around 30 psi and the high pressure side should be about 250 psi depending on your car. The correct reading will display once the clutch engages and the gauge stops cycling.

What does it mean when your AC pressure is on both sides?

If there are readings on both the high and low sides but they are not the correct specified pressures, it means that certain parts of the AC system are not functioning properly, such as the expansion valve, compressor, and clutch. AC pressure readings and what they mean