I just purchased a used 2003 MCS PP/SP/CWP with 56,000 miles from the Mini dealer in Indianapolis.

In 1st and 2nd gear at about 3,500rpm while I have the A/C on, I hear a pretty loud moaning sound that goes up and down as I increase or decrease the RPMs and it quits 2-3 seconds after I turn the A/C off. I would say it is a bad fan, but I am not sure why it goes up and down with the RPMs. Any ideas?

Dave

 

The moaning is the AC compressor, perfectly normal.

Steve

 

I started hearing this noise today for the first time. The weather was particularly hot 107C and in first and second gear I heard this noise. It stopped once I switched off the a/c.

Are you absolutely sure this is normal?

I am slightly concerned despite the fact that the car runs fine.

Thanks

 

Yeah i've been hearing the same thing on my '05 MC. It seems to get worse the hotter it is outside. I also find the longer im driving with it like this, the noise seems to get quieter...i guess it just works itself in over time...(or im getting used to the noise).

 

MINI uses a variable load compressor for the AC, the hotter the temp, the louder the noise. That is the harder the AC has to work the more noise you will hear. The reason for the noise lessening with time, is that the AC is not working as hard once the interior is cooled down a bit.

Steve

 

I had a grinding noise that only came on when the AC was running. It stopped when I turned off the car. I was sure it was an AC thing, of course...there was no noise when I drove (all day) w/ the windows down and the AC off.

What was it? The power steering fan! Crazy huh? The fan was replaced and now all is well. So much for my diagnostic abilities.

 

Don't feel bad, I did the same thing. I was sure it was the A/C. Power steering fan, just like yours.