AC Cycle

[darylfelsberg]

I searched the archives and didn't find anything on this trouble shooting situation so here it goes:

When I turn the AC, the Fans are turning on and off every 10 seconds or so. I can here the Compressor cycling with it and the relay clicking when it does engage, but the frequency is too much to use it in my opinion. I am afraid I'll ruin something else. So I have left the car parked since end of May. I fired it up again today, and the AC started that crazy cycling.

Please keep in mind, I may be naive when it comes to this, so if there is a "right there in front of you" fix, I wouldn't know it.
Thanks!

[DL4567]

Hi Daryl,

My first year of having my car, my AC worked great. The 2nd year, I started noticing exactly the same thing you are noticing. The radiator fans and compressor cycle on and off what feels like too often, and the relay click goes along with it. Then you start to worry about it. Over time, the cycle became even shorter, until it was just a few seconds apart. The relay click and cycle is more noticeable in the DeLorean than the average modern car, where you can barely tell the cycle is even happening from inside the cabin.

The #1 cause of short cycling is that there isn't enough freon in the system. When the system contains the proper level, the cycling should be around 30+(?) seconds on a hot summer day. This will decrease with cooler outside temps even with proper freon levels. But if it's cycling too often when it's hot outside, then chances are your freon is just low. That usually means there's a leak somewhere (I'm still chasing mine and replacing parts 11 years later!) and eventually when the freon gets low enough, the AC won't even come on when you turn on the switch.

Get the system topped off (or possibly evacuated and refilled) by a mechanic, and if they want to do some leak detection, great, but if not, the time it takes to start short-cycling again will tell you how fast it's leaking. If the leak is slow enough to where you only have to add a can a year, many people are happy with that.