Tyson2busy

Hi Guys,...

My air con compressor will come on every once in a while, then cut out. So I know it works, but what could be causing this?

Thanks

Rusty Spokes

Don't know what year model Audi..90..Cabriolet..but they work pretty much the same.

Could be low on refrigerant..compressor comes on and the low side pressures drop below the threshold of the low pressure switch..then the compressor kicks off..low side pressure comes back up..compressor come back on line and engages.

An over charged system will do it too. High side pressure switch kicks the compressor out when the high side pressures go up.

Some A/C gauges and an low side adapter (yellow jacket #19153 ACME FEMx13mm) on the compressor port will tell the story.

Tyson2busy

Interesting! Wow,..talk about a complicated system!

Thanks!

hubturn

There is also a thermal switch that will shut off the compressor if ambient temperature is too cold. If you are in the north country, it may still be too cold.

x19

What kind of refrigerant is in system R-12 or R134a?
In either way, lower refrigerant in system is doing this and check the leakage in system if you can
or let professional tech do the evacuate and recharge system with right freon gas includes leakage test. x19

egp320i

Sounds low, I had the same issue.

You should run the AC in the winter once in awhile to leg the PEG oil keep the seals lubed, helps to cut down on leakage.

Evac and recharge fixed the issue.