ClifordS

When driving the C300 W205 on highways, is there a difference between Sports+ vs Comfort when it comes to gas economy?

LAC300

Yes, the more aggressive profile of Sports + means your car will more likely downshift and use more power which would reduce fuel economy. How you drive is going to have a greater impact on economy than the mode itself (you can drive very aggressively in Comfort), but all else being equal Sport + will be less fuel efficient. I have no clue by what factor, all I know is that my C300 has excellent highway economy and pretty average city economy, but that's more a factor of how I drive.

miketc

On the highways, I don't think there will be much differences between Sports+ and Comfort if the mph are the same between the two modes because the gears are not changing (much). It will stays on 7th almost the entire time. This will all go out the window once you're in stop and go traffic.

BlackjackM

Mine doesn't go into 7th in Sports +, only Sport and below.

miketc

You're right it doesn't go into 7th in Sports+ right away but it shifts into 7th once it's cruising. Tried it this morning.

Zorq

I might be wrong, but on Comfort and Eco (or maybe only eco), the system will disengage the engine with the tranny to minimize friction caused and hence increase mileage. I expect to see mileage increase in this case unless you're constantly going uphill then it wouldn't make a difference.

BlackjackM

I will have to try it again

jakc

I don't think any of the settings other than Eco actually matters. It's all how you drive. If you drive gently on S+, it'll use around the same gas as being more spirited in Comfort. Keeping at 50Mph in 3rd or 6th gear uses the same amount of gas, it's just easier to accelerate quicker in 3rd or S+ than it would be in 6th or comfort.

Regardless I can't seem to get much more than 20mpgs in whatever mode I drive

Zorq

That is very wrong info. Accelerating in 3rd gear at 50mph will have higher rev, which means more fuel is used to rotate the engine, hence modern cars have more and more gears, one for more wide power band as engine is optimally tuned for a certain rev range, keeping the engine at the correct rev range by using multiple gears will enhance performance at the exchange of gear shift times. To be on topic, driving 50mph at 7th gear vs 3rd gear WILL have a impact on your mileage. In addition, driving in 3rd gear at 50mph will cause engine to have more load on the transmission as one of the laws of physics is the engine rotation will favour stopping as there's a constant energy loss during rotation which ultimately causes the engine to STOP rotating all together; hence the term "engine breaking" by using the laws of physics, we can increase stoppage of the car completely by lowering gear sequentially.


I'm not sure if I'm making any sense, but I hope that helps. Correct me if I'm wrong in the above explanation. Cheers!

Zorq

Just wanted to add some info from the web regarding driving economically. I skimmed over it but it does briefly explain driving at higher gear with LOW rpm will decrease fuel consumptions.




http://www.ecodrive.org/en/what_is_e...ving/#maintain