AC A/C Compressor short cycles starts and stops all the time

[Clovance]

Hey guys,

I got a problem with my AC again...
About 1-2 months ago the AC was serviced by an authorised mechanical workshop. I was there because it wasnt really cold anymore. I have been at 2 different workshops. The 1st one said the compressor is defective and i have to le it replaced - cost about 800$. So i got to another workshop and they said there was a leak at a valve and i was low on gas. Then they fixed the valve and regassed it. Everything has worked fine since then.

Today - as i stood with the car somewhere and let the engine run (idled) - i noticed strange noises from the front:
The AC - compressor runs and stops after maybe 1 - 2 seconds. Then after about 3 - 4 seconds it starts running again. All the time.
Inside it is not getting cold...

I already researched a bit, they said sth about short-cycling and low pressure...

So please tell me - what can i do?
Do you think i have to replace the compressor? It is a pretty new looking one and the last workshop said the compressor is very fine!

I also made a short video:
AC compressor short cycling - YouTube

Thanks in advance!

 

[The1]

Sounds like it is out of gas, as it ran fine for a few months it may just be another leak that wasn't found.

have a look around the a/c hoses and connectors for dust sticking, sometimes will alert you to a leak as there is oil in there.

 

[Clovance]

Well,

it was now exactly one month ago as the ac was regassed. Out of gas? The day before yesterday the AC worked fine, it was cold and so on. The last time it ran out of gas the AC worked worse and worse until there was no cold air anymore. It proceeded SLOWLY.

But this time from one day to the other the compressor won't work correctly! This is sth different for me.
Actually there IS a strange noise under my boot that i asked about at the last mechanical and he said it is just the air. It sounds like a leak to me. When i accelerate, then the noise is almost gone, it comes always back when i dont tap the gas pedal.

Do you think the last mechanical was wrong and this could be another leak? Or what is that?

And i also noticed, that im losing just a little bit oil out of the radiator hoses, as i uninstalled and reinstalled them for installing a new water pump (to have more space to work).

But i dont think this problem could refer to the AC problem right?

The A/C hoses are all okay and look good....

What would you recommend?

 

[accentstencil]

Recently my aircon went from being cold one day and and not cold the next, so I went to get it re-gassed and was told my compressor was stuffed (it was also make an unusual noise), replaced the compressor and all good again.
Perhaps the first mechanic was right.

 

[Nut Kracker]

Just a thought.
If the system was low on gas, I don't think the high/low pressure switch would allow the compressor to turn on at all.

Try this.
Open the fuse/relay compartment in the engine bay and find the A/C relay. There should be a diagram of the fuse/relay location under the cover.
Start the car and turn on the A/C as in the You Tube video.
When the compressor is cutting in and out, put your hand on the relay and feel if it's cutting in and out in time with the compressor.
If the relay stays on, there may be a problem with the compressor.
If it cuts in and out....well who knows. Sorry.
Something easy for you to try.

 

[Clovance]

Hahahahhahah
U want to know what was wrong?

One cable to the front fans wasnt fit it
I plugged it in and now everything is fine! Cold air

 

[Nut Kracker]

Well, there ya go.
Simple fix. That's what I like to hear.

 

[Nut Kracker]

Sound about right actually. The ecu was trying to start the fans when the a/c was on, it found it couldn't and switches the a/c off.......switches back on and tries to start the fans again, couldn't, switches back off and the cycle keeps repeating itself.

 

[G-dogg]

what pins are used in the relay to jumpstart you compresser clutch, to test it.

 

[Nut Kracker]

Pins 3 and 5 on the A/C relay.