downhill driving button turned on

[mtb9153]

I have found that driving with the downhill button pushed on allows me better AvMPG numbers. While driving on fairly level city streets at 35-40mph within a city block I saw my numbers increase from 43 to over 60. My question is does it hurt anything by driving with it turned on for longer periods after the road levels out. There just seems to be more increases in my tenth of a mile digit over when it is turned off. With it off if my numbers drop down to 43 and I push the button, right away the .X number starts increasing steadily. Has anyone noticed this?

[Tdefny]

Say it again?

[Tdefny]

I couldn't resist

[mtb9153]

Excuuuuuuuuse Me LOL  I don't know why it posted twice, sorry :doh:

Edited March 14, 2014 by mtb9153

[Tdefny]

Nevertheless, I think I will have to pay more attention to that mode.

[Tom]

I have found the down hill button to be very useful for its intended purpose -- to hold /slow vehicle speed while going down grades -- or just coming to a stop on a level grade.  When I use it in steep declines, it sounds like the engine is revving up which I assume is the engine braking.  A feature I quite like.  I was reluctant to buy a car with an automatic transmission that did not include a mid range gear that I could shift into for this purpose.  When I learned that the C-Max had this down hill feature, I kept it on my shopping list and ultimately bought one.

 

Well, I ramble on, but to get to your question, I think that if you use your down hill button feature as much as you can, its use, while slowing you down, also sends some amount of energy to the battery thus reducing the need for the ICE to operate to recharge the battery.  A gasoline saved technique, perhaps.  To use it on a level road where you are not intending to slow /stop would seem counter productive.

 

Your thoughts?  

[fbov]

As I recall, downhill assist (DHA) only works when you're coasting, and then only to keep speed from increasing. If you're got your foot on the go-pedal (Can't really call it the "gas" anymore, can we?), there's no effect, ill or otherwise.

 

What you're observing, Mike, is different behavior when coasting, but not down steep hills, right? Granted an MPG change takes distance to become evident, so you'd have mixed terrain by definition. I find very few lift-throttle hills around here; most are just EV-assist.

 

Reading more carefully, you're seeing a short term phenomena: "...within a city block I saw my numbers increase from 43 to over 60." The only time I see the MPG display move that fasts is right after a reset, when there are very few miles, and even fewer gallons recorded, so a little EV mileage can drive high ratios.

 

I'll have to try it myself.

Frank

Edited March 14, 2014 by fbov