Whats the difference between Comfort and Sport mode?

[television]

Yes, isn't that odd. Could someone technical explain why some few years back turning off the aircon made a big difference to consumption and now on models over the last few years it is hard to detect any significant gain? And what a difference in misting up etc as Whitenemesis says.

On earlier car the compressor clutch only engaged when you turned the air con on.
For the last few year and more so with climate control the compressor runs all the time (no clutch). that I why there is no difference.

 

[verytalldave]

I didnt know that. Thanks Malcolm.

 

[television]

I didnt know that. Thanks Malcolm.

I think Dave that you could take this 1 step further, if you turned the temp to minimum, then the compressor would be under load, but this could be so slight it would not be noticed.

I often read of summer motoring tips given out by the press, turn the A/C off to save money, what a tip, 2 screaming over heated kids in the back, you are too hot to think, and you paid a couple of grand to have A/C. I think it is a bad tip

 

[jberks]

I've been running in C for a few days now and yes it does improve economy. 27 has become 29 on my short conjested hop into the office.
That said, after 2 years running in S, I've eased my foot down expecting a spirited take off a couple of times now and found the response lacking. It did pick up eventually but the kick in the back I'm used to didn't arrive.

 

[verytalldave]

There has to be a trade off. To get better economy, performance generally does suffer somewhere down the line. However, you do get used to the slightly slower pickup and modify your driving accordingly. Personally, I prefer the less aggressive delivery of C mode. And as an added bonus, I have been reliably informed, the rear tyres last much longer. MUCH longer.

 

[moneyman]

Tend to use C on my CLK 500 for the majority of the time. Power delivery is much smoother also better on wet roads as you can light up the rears in S mode without trying. However with the right conditions S is fine and provide plenty of

As for fuel economy I think that the difference is negligable. I have just completed 20k miles at an av of 25.7mpg which I consider to be v. good.
Regards
Steve

 

[hawk20]

On earlier car the compressor clutch only engaged when you turned the air con on.
For the last few year and more so with climate control the compressor runs all the time (no clutch). that I why there is no difference.

Thanks from me too Malcolm. Interesting to learn why on recent cars it makes almost no difference, yet years back the difference was significant.

 

[whitenemesis]

On earlier car the compressor clutch only engaged when you turned the air con on.
For the last few year and more so with climate control the compressor runs all the time (no clutch). that I why there is no difference.

Thanks from me too Malcolm. Interesting to learn why on recent cars it makes almost no difference, yet years back the difference was significant.

I realise I could be arguing against my own findings but..

Reading through the docs re the aircon, it is running all the time but there is a valve that releases the load on the compressor when not required. I would have thought a free spinning compressor would present less load akin to when there was a clutch?