I've noticed some peculiar issues that my car (09' MCa) has whilst engaging the AC. Today, as I was entering the freeway and turned the AC on there was a sudden :: clunk :: and the car jerked (well, I assume it was the engine compensating for the extra power needed for the AC system?). Is this normal?

Also noticed that whenever the AC is on the car is extra jerky to drive and seems to struggle a lot more, especially uphill. It's just more groany and stuf... anyone of this normal?

 

I haven't noticed any of these symptoms...

Really sounds like something to be addressed by your dealer at the earliest opportunity (if no simpler explanation comes out). Good luck.

 

I have the MCa and I have not noticed any problems in that area.

 

We have an 09 MCa Clubman and a 08 MCa Cooper. No issues with our auto-air in either MINI.

 

Shouldn't be that noticable at all. Sounds like your air conditioning compressor is robbing way too much power. A barely audible clunk is normal when you turn on the AC as air conditioner clutch under the hood pulls in to make the engine turn the air conditioning compressor - but you should really have to listen hard to detect that.

 

That's what I thought...

The whole car jerked and made a loud noise when it was engaged as I was entering the freeway. However, if you turn it off and then turn it on again all is fine. It seems the initial powering on of the AC causes the most reaction, but not subsequent uses during the same drive.

Made an appt. with dealer to have it checked tomorrow. Will update.

 

I have the Auto A/C in my car and I will actually click on and off the A/C button as I get too hot or too cold. I rarely adjust the actual temp button. I'm under the impression that the A/C button when switched on can reduce fuel economy...

I've actually noticed no lag whatsoever when turning the A/C on and off. I obviously hear some noises within the unit itself, but the engine doesn't seem to suffer at all.

My 4 Cylinder Honda will shimmy a bit when I kick the A/C on and it seems to lose a little in the performance area as a result. I've even had the ligts flicker some when turning it on and off. The Mini hasn't suffered a bit though...


I will say this... If it's more than 80 degrees outside, the A/C has to be on high in order to feel anything at all. The fan is fairly weak in comparison to other cars I've been in..

 

Well... dealer said car is fine and any jerkiness etc.. is totally normal. Hasn't been as bad lately, but then again I've been driving the car a lot more lately. who knows!

I still love my MINI <3

 

Mine's in the shop now to replace coolant, plugs and wires, add PS fan guard and replace the belt tensioner, which my mechanic says was causing the shuddering I thought was my AC compressor. My compressor is also cycling way to frequently, but they don't know the issue for sure, yet. I know the shuddering happens when the AC is on, hven't noticed it when it's off.

 

Watch out; jerkiness can be an inherent dealer issue.

 

Well, the compressor is doing the shuddering, but it works, so it's staying put until it fails.

 

Hi 22, you shouldn`t feel a thing when air-cond cycles or switches on. As others noted, turn them off for a while when cool enough, on big hills or flogging it. Try a more customer oriented service dept. lvspeed

 

A small sensation is normal when the A/C first comes on, but after that you should not notice much. You will notice a slight loss of power.

 

On my '09 Clubman S I'm delightfully surprised how little difference the A/C makes, on my '03 MCS it seems like it takes away about 20% of the HP, and really makes it sloggy from a start - by comparison. I also notice no difference in the fuel economy - and yes, I'm sure it's working!

It's funny how if the car has been sitting in the sun on a really hot day, the A/C can barely keep me cool, and that's only on Max. If the car's been in the shade, I have to dial it back sometimes........

I've never felt it engage, again unlike the '03 which can give a small jerk when the A/C compressor clutch engages.

 

almost all new cars have Electric A/C thus they are not a pulling off the engine so when they hit load or spin up they are drawing down the alternator which is already spinning on your motor. that is why you do not feel sutch a sap in power when the A/C is running. The old belt system when it engaged it was add resistance to the motor even if it was just idealing not fully in a compression cycle.

 

..I'm pretty sure the MINI's A/C is still directly engine driven. When the A/C is turned on you can feel a definitive jerk as the A/C clutch engages.

The sap on the Cooper's power is not that bad (compared to our Civic). Uphill I typically turn it off (though it's not necessary, really) and sometimes in stop-start traffic (makes starting easier). I almost wish they gave it a beefier compressor to make the A/C stronger--I could live with a bit more power drain.

 

Yep, it's still engine driven, I can feel it engage and my engine feels slightly more loaded but the overall effect is barely noticeable.

 

Small aircraft often use AC systems driven by an electric motor that is powered by the alternator rather than a drive belt connected to the engine. Our MINI's are still belt driven.

Even with a system like those on some small aircraft - turning the AC on still robs power from the engine as it makes the alternator harder to turn. The power still comes off of the engine - just not directly as with a belt. The battery will soften the initial shock load better than when the compressor is belt driven - but that is all it will do.

Ever notice the idle speed of the engine on older cars without fuel injection that did not automatically adjust their idle would have a slightly lower idle speed when we turned the headlghts on?

On my S I can't detect the AC compressor but if I listen very closely I can hear the faint click of the compressor clutch pulling in.