When I run any form of air through the control, besides the vent option, it makes the engine rev up and down constantly and I can hear the compressor clicking on and off. Has anyone experienced this also? If so, what was the fix?

Thanks

 

How often does the compressor turn on and off? What is the range of rpm?

George

 

Every few seconds, not sure about the rpm's, I don't have a tach. It is doing this during idle and is very noticeable and does this during driving as well with a huge decrease in power.

 

It is normal for your ac compressor to cycle under certain operating conditions but not every few seconds. Most of the time this happens when the system is low on refrigerant. The compressor engages and the low side pressure drops very quickly because of the low charge and goes below the cycling switch cutoff value. There are other possibility and a proper set of gauges is the only way to properly diagnose. Just adding gas can actually be dangerous if the system does not need it.

That said, this should not increase the effect on engine speed unless the compressor bearings are failing and presenting a large drag on engine speed and power. A few of the Other causes of all that rpm hunting can be: throttle body, IAC valve, vacuum leak, slipping serpentine belt, …. Most of my normal suggestions don’t apply here because you lose power when the AC compressor engages which is very unusual. I assume you mean while driving.

If you have a set of gauges, monitor system pressure during cycling and correct the system pressure if low. Check your belt and tension. Scan for codes. Report back.


George

 

Thank you Sir I appreciate the information, while at the mechanic a few months ago they recharged the system but alas that did not resolve the issue I'm having. I will check the other items you have listed and move forward from there.
Thanks again

 

So the system was prefessionally charged and the compressor still short cycled?


George