CL55NYC

Has anyone else noticed the substantial decrease in power, pickup, and gas mileage with the AC on?

I know that it affects many cars but it seems like the AC unit in the CL55 just drains the car down a great deal. My gas mileage is almost cut in half with it on, there is zero kick when I hit the pedal and the engine appears to be a lot louder.

Curious if anyone else has noticed this.

awiner

With the temps here in So. California in the 100's for the past 2 weeks, I have had my AC going non stop. My gas mileage went down maybe 7-10% . Have not noticed a difference in pickup/power at all with the AC on however.

victoryroad

I have not run the car with the AC off yet, but will to guage performance differential. My gas mileage has been around 15-16 mpg, and obviously a lot better on the highway, but that is with the AC on. I would not have expected such a large drain on output with AC on given the engine's torque. If I get into any contests, I will shut AC off. So far have not had any problems with it on when I have had the need for speed.

Harris

Umm....not only on a V8 kompressor. Same thing happens on a V6 Kompressor too!!! My car feels like a C320 during hot weather with AC on.

victoryroad

I turned off the AC yesterday and the additional power was very noticable. Have not gauged gas mileage with AC off. Funny that I have driven every other car that I have owned with AC off just to see the power difference, but it did not occur to me that the drain of the AC would be so obvious on the CL55.

Kain

Does anyone know a possible reason for this?

stephens

On the dyno there is less than 10kw power difference between A/C on and off. I left the AC on by accident and saw very little difference.

victoryroad

Stephens
At what rpm did the you measurre the difference between AC on and off on the dyno? My car is more responsive with the AC off at normal orerating speeds.

Kar don

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corgiman

FYI - the engine control module TURNS OFF THE A/C compressor at WOT for about 45 seconds to give full power. Just push the pedal to the metal!

victoryroad

Does the system turn off the compressor at less than full throttle? If it does not, running with the AC off provides noticably better throttle response in normal operating ranges. For those who have driven the CL55, full throttle is not necessary for the vast majority of driving situations. At highway speeds, I have used full throttle more than at lower speeds.

corgiman

I would guess it disables the A/C only at full throttle.

CL55NYC

I have used full throttle without the AC on just 3 times...great experience.

With the AC on, it requires you to "push" the car a great deal more and even when in lower gears through manual transmission, there appears to be a "gap" in the repsonsiveness of the engine catching up to the position of the pedal - I hope that makes sense.

As well, not sure if other people have noticed this but the engine runs considerably louder with the AC for an extended period of time - the RPMS arent accelerated but the engine has a much louder hummm to it.

Anyone notice same thing?

victoryroad

I have noticed the louder exhaust note with AC off. Quite awesome. Makes me feel a bit like I'm in one of the pony cars of the 60's when I was a kid and could not even aford a VW.

ajayz

thats odd, I didnt think that should be happening in newer cars?

victoryroad

It is not odd when you here the exhaust note from the CL55 under half or more throttle. It is exactly what I want to hear. Not the whine of the 360, which is awesome, but a deep powerful sound that makes the driving experience much more engaging. Not as visceral as the 360 or a 996 TT or a NA 996 with the new Sport Exhaust, but very nice.

ima55r2

On one of my previous cars, G-tech runs showed a 50 hp loss (325 to 275) with the AC on. I can notice the difference too on my clk.