First week with the update: a little faster

[mlaurence]

I just finished my first week with the FE update. Before it was installed, my C-Max lifetime mileage had just hit 45.0 with 1700 miles.  It's been steadily going up.  After the update, I did a 200 mile week total with 35% interstate, 25% highway, and 40% stop-and-go city driving.

 

The city and highway driving is pretty much the same as before.  I think it's a little faster to go into EV when I get going, but that's offset (so far) by the lack of EV+ when I get home.  Those settings got erased with this update.

 

The interstate is where I really wanted to see something.  I had a 120 mile trip that I've done most weeks I've owned the C-Max. I can get 45mpg but in the slow lane, getting passed by everybody at 62mph - including the Priuses.  :(  Now, I was hoping to get the same mileage at 65-67mph.  I tried ECO at 67, and watched mileage dip into the 30's for the first time since I bought my C-Max!  Nice to keep up with traffic, but my post-update mileage was struggling to stay above 40. For the first time my lifetime FE dropped, only by 0.2mpg but I was not happy with this update!

 

On the way home, I decided to drive the car myself.  No cruise control, do what feels right.  On the 60 mile trip I descend 900 feet overall so FE is bound to be better, but I was happy to bring my overall mileage for the week to over 45.  That's more like it!

 

This is what seems to work: drive with much the same strategy as in the city, but faster.  Push to 70+ with the ICE, then coast and gently push with the EV until a hill or low battery brings on the ICE.  When I see that happen, push a little harder back up to 70 or more and repeat.  Oddly enough, the cruising coach doesn't like this at all!  I spent most of the trip on the halfway mark, the coach turning yellow with every attempt to go over 65. Even when I'm going downhill and the EV is going positive, Coach was still pissed!  It seems he won't calm down until I go below 63 in the slow lane and get passed by everyone.  

 

But if I just keep doing what feels right, I'm still getting better mileage on the interstate than I did before the update.  I'm happy to see that at least some of the time I can drive 70+ and still keep the FE where I want it.

[asb]

I drive using the ECO cruise pretty much all the time.  After the update, I had hoped to see the numbers that everyone else was seeing in the city, but it hasn't worked out that way for me.  The first tank was great.  After that, my mileage just keeps dropping.  I guess I need to adjust how I drive more??

[mlaurence]

I don't see much difference between ECO and every other cruise control I've ever used.  It slows you down a little bit on hills, but for good mileage I'd slow down by 10mph or more.  What you can do is push it a little more when you see a hill coming up, then ease up on the gas (not all the way, but somewhat) and accept that you'll be going quite a bit slower at the top of the hill.  But once the gas engine kicks in, feel free to push it when you get close to the top of the hill.  Then when you get to the top you'll be back to the speed limit or above it, and you can coast on EV for a while, building the mileage back up, making up as much as you can of the loss from that climb.  

 

It's so important to be able to anticipate what's coming up.  That's what gives us human drivers better results than the ECO cruise control.

 

At least that's the way it looks to me.  But hey, I've had the update for a week, so I'm still learning.  Maybe there's a better way - I'm sure I will learn some new tricks as I go.

[mlaurence]

Now I have my first fill-up after 400+ miles with the update.  And it barely made a difference in my lifetime mileage.  My tank was 0.3mpg under my Fuelly average, which didn't change things from the previous 44.1mpg.  The car's own computer didn't change either, still 45.0.

 

The really good news for me is that I did not spend the whole time in the slow lane trying to hit this number.  Instead of driving under the speed limit all the time, I was going 65-75 as I let the EV kick in to coast for a little while on the interstate.  Probably my average interstate speed was a little over 65, which makes a considerable difference when everyone is going 65-80.  

 

I still haven't gotten the rhythm quite right. But I'm encouraged:

 

I didn't lose mileage - well, a tiny bit, but that's just a glitch.  

 

My EV+ is back after it disappeared for almost 2 weeks after the update.  That little EV boost when I get close to home really makes a difference.

 

Considering that I was really experimenting for the first 1/3 of the tank, I think the mileage will be heading up in the future.  The best news: it was only a tiny drop.  45mpg is a lot better than I expected when I bought the C-Max, and I'm still getting it in the city and - almost - on the highway.  I'll get that 47mpg yet - although with winter on the way, I might have to wait a few months.

 

 

[BobJustBob]

Because I do so little highway driving, I had not seen any noticeable improvement in FE after the upgrade--until this week.  We've been experiencing an early autumn cold spell in Pennsylvania, and the temperature has been in the mid-40's the last two days as I departed for work in the morning.  My unscientific impression is that I am getting slightly better gas mileage than I would have had I not gotten the upgrade.  Both days I got in the mid 50's mpg range going to work (my drive is primarily downhill going to work).  Since the upgrade, I've been keeping track of my mileage going to work on a spreadsheet.  I'll have to post that soon.  Unfortunately, I started keeping track only after getting the upgrade, so I don't have hard numbers to back up my impression.