My (03 build) 2004 Cooper makes an awful whine when I accelerate with the AC on. It sounds like what has been described here. I don't remember it making this noise until I had used the AC for several months. Now the sound seems louder, but it could be that I am just getting more irritated with it. I'm close to my next service so I'll mention it then.

I Found This Thread With The Search Feature!

 

Thread revival!

Since warmer weather is approaching, and though it is nice to cruise with the sunroof open and windows down, sometimes it just too darn hot and I roll with the air conditioning on. I purchased my 05 MC in December, so this is my first warm weather experience with the vehicle, so all these sounds are new to me.

The specific sound in question is the loud whine heard while accelerating, especially above 3k rpms. Some say this is common, but is it good common meaning it is normal and nothing is about to blow up, or bad common like a leaky thermostat housing or coolant reservoir?

Any opinions on this?

 

Hey guys,

I have a 2004 MCS that has just started (this spring) making this crazy pitch changing noise only with the AC on. It goes away with the AC off after a bit.
Of course I can't get it to make the noise when I am stopped in the driveway with the bonnet open!

I am familiar with the regular lovely high pitch noise of regular AC use. This is different and slightly embarrassing. Engine revs don't change it, but it does seem to increase slightly stopped at traffic lights.

Any ideas?

 

Any updates on this issue?

 

I have the same problem on a 2003 MCS, its almost like a vibrating whining noise above 3k RPM when things get really hot, it is only intermittent right now, but I have no idea what it is....