On my 09 FWD FEHL it seems that any highway driving is really bringing down my mileage averages. When I first picked it up I averaged 40 MPG bringing it home and running a couple errands. I had to take a road trip that weekend, probably 200-250 miles on the highway at 70 MPH. My average ended for my first tank at 32 MPG. Now I have my scangauge hooked up and my instant MPG on the highway is usually at 28 - 32 MPG getting up to 36 with some draft and 40 - 45 downhill. With any incline or extra wind resistance its down into the 20's. I only have 600 some miles on it, does it need more break in?

I've used the cruise control and the instant readings are the same. I've tried to use the fake shift to bring the RPMs down but then I'm losing speed because the engine won't hold the speed at the lower RPM. Any suggestions?

 

Personally I think it does much better between 55 and 65 on the highway and that above 65 really starts to put a hit on your fuel economy.

However I think you really have to use your SGII to manage your RPM's and use your P&G wisely to get the bounce you want to your MPG. I do not use CC that much but have noticed as GaryG has commented on that I will see my SOC rise as my rpms are dropping on the highway and get pockets of interstate driving where my SGII will read 9999MPG. Overall I am averaging greater than 31 on the interstate but I really try to watch my acceleration on ramps and in/out of traffic. I try to not drive like I used to and be environmentally friendly but at the same time not trying to tie up too much traffic behind me.

 

I just did a 200mi one way drive in my '08 FEH and the NAV reported 41.1MPG. This is on a four lane divided highway and for a large portion of the drive there were no other drivers around. The drive is rather flat as it parallels the coastline. I was in no hurry and I kept my speed between 45-60 the entire way (45 where it was the psl). This is with E10 gas as well. I used the FS, P&G and tried my hand at ridge riding as well.

That said, I've made the same drive (when I was in a bit more of a hurry, 50-70MPH) and only gotten around 32MPG. I agree with Patrick, speed is your worst enemy here.

 

Desertdog (CarlD) told me how to check the type of 02 sensor by entering a code into my SGII. After I did, the next day I noticed a big decrease in mileage. My SGII went to sleep and then I knew my SGII reset itself to the default settings. Make sure your SGII is properly set-up for the '09 FEH.

While driving at highway speeds I use every trick in the book to stay on top of my mileage. This includes coasting, safely drafting, P&G and anything I can do to take advantage of traffic. Just because your FWD FEHL is EPA rated at 31mpg does not mean you have to except that mileage. On long highway trips I've averaged 45mpg in my '05 FEH. Even in a rush of time I've gotten to my destination with great mileage by driving smart and taking advantage of fast moving traffic and slow moving traffic when the time comes. One technique does not work but a combination of all the techniques at the right time seems to work for me. I remember one day I had to get downtown from my house 20 miles away in rush hour traffic before the courthouse closed to pick-up work in 30 under minutes. I got there in time and averaged 47mpg from a cold start. That surprised me because I didn't even have time to look at the SGII on that trip till I got there. My speed got up to 70mph on the highway also during that trip.

GaryG

 

I definitely agree that there’s a big difference between 55, 60, 65, and especially 70. I try to keep my speed down as much as I can. I'm going to check my fuel type I have set, thanks for that tip on buleoval Gary. I'm going to work on using more of the techniques on the highway, I've been working hard on my city driving and I've kept this tank at 37 MPG so far. I guess I'm used to squeezing highway miles out of the old Jeep with a regular transmission and I need to adjust more than I thought.

 

I'm pretty sure the guy who sold me my car told me not to use Cruise Control until after 1000 miles. You probably shouldn't be using it yet.

 

His comment is very true for a conventional vehicle using manual transmission or automatic with lock-up. A constant speed means a constant engine rpm, which is not good for break in.
However, the FEH or any other THS vehicle's eCVT does not have any lock-up mechanism, therefore we won't see a constant engine rpm even by a constant speed.

Anyway, as everybody wrote, speed is an enemy for good mpg.
There is no magic here, slower speed is better for mpg and higer speed is worse for mpg above 42mph on highway.

Ken@Japan

 

Some notes on things I've noticed. When coasting my scangauge only reads 9999 MPG when my SOC is 48% or higher and the coolant temp is 170 or 180 or higher in natural and will read something like 132 MPG when the SOC drops below that and generally in D it will stay at 9999 MPG as long as the SOC starts at 48%. However, this doesn't always hold true, at times I find myself meeting those requirements and the MPG will not go to 9999, any ideas why?

One thing that happen to me on a longer journey on a stretch of mostly flat road, I'm usually always going up a hill around here, the battery charged quickly to 55% and then dropped my RPM's to 1500 at 65 MPH and provided electric assist at about 15 A down to about 48/49% giving me 75 MPG instant readings. It did this twice before I was back into hilly sections. The only thing I could notice was that the battery charging was occurring while I could keep the RPM's just under 2,000 so anytime I hit an incline it stopped. Is this supposed to happen normally, or did I get lucky? I haven't been able to recreate it on the same stretch of road. This same event however did just happen to me again this morning on a stretch of road I would normally drive in EV but due to the 14 degree temps this morning the engine refused to shut off at that point. In addition, I had a much higher than normal SOC because of a couple short drives in the cold weather over the weekend. On the stretch my SOC was again up around 55/56% but this time the engine was revving at 2,000 RPMS with assist of 15 A but my instant MPG were still in the 40's at about 37 MPH. Is this normal behavior when the SOC gets up that high? Anyone else experience this? I don't think it would have to do with a reconditioning, I only have 2500 miles on the vehicle. Thanks for the comments!

 

When your SOC exceeds 53%, the vehicle will act to bring it down below this level by using hybrid battery assist and/or spinning the ICE. Ford designed the vehicle this year to promote durability of the hybrid battery and has nothing to do with reconditioning. If you take a peek at the Honda section, you will find reports of hybrid battery failures or issues before 100,000 miles.

 

Does Honda use same Sanyo battery as Ford?