My 2003 Cooper is very odd with the A/C on. Sometimes the lag is unbearable, other times it is hardly noticeable. I'm not sure what gives. I can understand the frustration for somebody in Fl with a long commute.

 

IF the AC doesn't have to work to hard, it cycles on and off. You're just lucky that some of the starts are with the compressor off.

Also, the comment that the stock MC/MCS is like a lawn mower off the line wiht AC on.... My lawnmower doesn't bog......

Kalaria is right. ECU programming blows.

Matt

 

Kaelaria described my situation exactly. In my opinion, with the AC on, this MCS is a dog off the line, "unless" you get the revs up significantly before you want to pull out. And, in stop and go traffic in this area, it is my biggest complaint to date with this car. I was hoping the 15% pulley would help, but it didn't. Interesting that the program fixed his issue, certainly worth considering. The slow rev of this engine is suprising as well, wish it could rev quicker, more like a weedwacker. Perhaps GIAC, MTH, etc will help me out. I do notice at times that the idle picks up from say 800 to 1,000, and that helps a bit. I figure that happens when the cooling fan kicks on. If the idle simply went to 1,000 the whole time the ac was on, that would help.

 

MTH is a software upgrade



Art

 

My '04 MC has a noticeable loss of power when the AC is on, moreso than I have noticed in previous small-engined cars I've driven. It is a bit disappointing, but fortunately I really only need the AC for 2 or 3 months a year where I live.

 

2005 MCS 6 spd

NO A/C: I can "rev" to around 1000 rpms and let out on the clutch for a nice smooth, easy take off.

A/C ON: I ALWAYS make it point to bring the engine revs up to 2000 rpms and then let out on the clutch. Less than 2k rpms and the engine wants to die and/or I'll briefly get the bucking-heaving-hesitation complex.

Driving aggressively, however, the MCS with or without A/C is good and strong.

Dave

 

'02 MC CVT w/AC on... SUX!! MPG goes down about 3-5 and power is out the window

'03 MCS w/AC on prett much the same and not much change in MPG

I don't turn on the AC until I put on the auto pilot on the highway in the MC

 

I haven't seen this mentioned yet - does it apply to an 03

Try bumping it over into Sport Drive when more power is needed. This seems to help my 2005 MC CVT greatly in situations such as highway merging, driving with AC, or keeping up with the MCS's in the local road rallies...

Jim D.
2005 MC HB/W

 

I have a CVT MINI and I do notice a drop in performance with A/C on. What I do on start up is nail the throttle to the floor, past the kick down 'detent'. Then before the engine shifts at 6k RPMs I let off and keep the RPMs high. This method isn't quite as quick as it is with the AC off, but for most normal real world driving scenarios, it works pretty well.

 

We have an '05 CVT MCC (in Dallas area) and yes we've noticed the power drop this summer. I don't always drive in SD mode to save a little bit of gas. But, when starting out from a dead stop I flip it into SD until I get over 30 MPH and it settles out.

SD seems to bump the RPM about 1K, and seems to have a little more power starting out. However, if I need a quick entrance to the freeway, I leave it in SD and just tap the A/C button to kill the compressor long enough to get up to speed with the rest of the traffic. If I'm in a mood to do a little more "spirited" driving, I drop the top, kill the A/C and leave it in SD mode. The breeze is just fine at 65 or above