[carrots99]

Hello,

I'm having a problem (reincident), that I would like to know if someone had a similar problem like mine or has a clue of what this is, it happened for the second time:
usually the days are getting colder, so I haven't been using the AC often. this weekend though was a bit hot, so I used the AC. On the second day driving the car and using the AC, the engine, when accelerating, starting to make something like an howling / whining sound; even if the car was stopped and the AC off, you would hear the howling sound everytime time I accelerated. Today, the noise as stopped and, coincidence or not, the AC stopped working, it is just blowing warm air instead of cold. Last month the same thing happened, I went to Citroen, and they told me it was the AC that had too much gas, it should have max 400 grams of gas, it had 664 grams (at that time, the explanation sounded like bullsh**t to me). Now, a month later it happened again.

Does someone have the slight clue of what it might be??!!

I found two videos on youtube where the sound recorded is similar to what happened to my Cactus:

[URL=https://www.youtube.com/watch?v=bqedXPjZ6fE]

Thanks in advance

 

[BristolRich]

A whining noise is hard to diagnose without looking at the car.

It could be one of many things, however I'll hazard a couple of wild guesses and say that if the pitch increases and decreases with the speed of the engine then it could be belt or bearing related. The aux belts on the car will drive the power steering, alternator and AC compressor (that why the AC cuts out on Stop Start) and it might be that it is too tight or that a bearing on one of the driven components is under stress and failing. That said it could also be the alternator under stress as a result of a busted compressor and working over time to compensate for a high current draw on the battery.

or...

The fan unit inside the heater box is duff and making the noise, or that the stepper motor inside the temperature direcetion/ control valve mechanism has had it (not an uncommon fault on the C4)...

It could be anything...you best bet is to take it in to your dealer and get them to look at it. It is under warranty after all.

As an asside...AC isnt just for summer you should use it in winter time too as it prevents the windows steaming up. Only below cold temps (IIRC 2deg C) it automatically switches off unless you select front screen demist. Plus leaving it switch off for long peridos of time causes issues as the gas contains lubricants for seals and components.

 

[carrots99]

Thank you so much for your feedback. I went to the dealer this morning and it turns out that you were right about your first guess. they are going to switch the compressor and the belt!!! At first they were saying that the AC malfunctioning could be a leak in the fluid, but than they figured out it was something else...

Now lets wait for the parts to arrive, lets just hope that after fixing it, it doesn't happen again!!!
Now I have to leave my dear Cactus parked and let it rest for a few days until the compressor arrives...

Again, thanks for the feedback!