Hello all,

I have had my 2008 FEH for about a month now, I love it.

I would like to start a discussion on any insights for optimizing mpg's on the 2008 models. I have lots of large hills which I believe are affecting mpg's, averaging about 30mpg with 700 miles on the vehicle.

I have noticed that I am registering RPM's (not EV) when the navigation hybrid menu shows the ICE is NOT running (especially when going downhill)? I thought the RPM's were measuring info. from the ICE?

I have also tried shifting into neutral going down large hills on the x-way, it didn't seem to change the mpg's, but the nav screen max is at 60mpg either way.

In terms of accelerating to 65mph on a highway ramp, I know it is better to accelerate slowly but sometimes that is not an option for some highway ramps. I have tried fake shifting, but I'm not sure if that is working ...and it makes my wife sick?

In city driving I feel am doing pretty well by keeping the hybrid system in EV mode up to 30mph. I do have to press pretty hard on the brakes (two taps on the brakes) to get it to switch over to EV, hopefully I can become more subtle at this or the vehicle will become more sensitive.

Any other suggestions for improving MPG's on the 2008 model?

Thanks,
Brad

 

Please browse all the threads on this site.
Any tips from years 2005 to 2007 will also apply to your 2008.
The powertrain is the same in your car as all previous models.
Only minor refinements and cosmetics changed for 2008.

Your car is not broke in yet.
Both you and the car will get better MPG's after 3000 miles.
-John

 

Until you have at least 3,000 miles on it don't expect any of your measures to have much effect. That said, keep trying because it will be good practice for once your vehicle is "broken in". The 2008 is the same system as the 2005-2007 models with a few little software tweaks. Any "tips" for the earlier version will be effective on the 2008 as well.

As for the RPMs....what you are describing is correct. When the ICE is running you will see RPM's on the TACH. When the ICE is off the Tach will drop to the green zone below zero. There will be times in EV mode that the ICE will start turning to burn off excess charge. If your battery is full...and you are coasting downhill regeneration will top of the battery and then the motors will spin up the ICE to prevent overcharging.

Several people who live in mountainous regions (gpsman) report that lots of hills have a positive impact on mileage. I see the same thing when driving over large bridges. You get low MPG on the way up but big numbers on the way down. Overall, it is better than flat driving.

 

My 08 is a week old now. It takes a pretty potent double tap for me to achieve ICE off too. I have also tried releasing my foot off the gas and shifting to L. That seems to cause ICE off with greater ease than the double tap.

So far in my last 100 miles I am getting 34.something mpgs. I feel like I am driving like my grandmother's grandma to pull it off though...

 

These are all good points that will help you increase your mileage. Just don't listen to the "clowns" who will try and convince you to "draft" (tailgate) to increase mileage. This is very dangerous and not worth the slight increase in mileage. Happy voyages!!!

 

I've had my 08 FEH 4WD for about a month and a half, and I noticed a week ago (~1600 Miles on the car) that things seemed to be better on the MPG front. Now, I was doing "okay" beforehand ... "lifetime" average between 32 and 33 MPG ... but is this is the "amazing breaking-in" that I kept hearing about?:

1) My last tank the NAV was a lot closer to my hand-calculated MPG than it had been for the previous two. Tank #1 was almost identical, Tanks #2 and 3 the NAV was well off, and Tank #4 is back to being a bit closer.

2a) The FEH goes to EV faster. I have a nice 2.5 mile drive to/from the expressway each day, with only 3 stoplights and a speed limit of 25 or 30 mph. Once the car is warmed-up (in the morning), the ICE shuts off quicker when just coasting than before.

2b) The FEH goes to EV at higher speeds. For the first month of ownership, even when the engine was warmed-up and the battery had plenty of charge, I couldn't get the ICE to shut off until I was at almost 30 mph. Now, when I'm on a highway exit ramp for example, I'll look down and see the needle drop into EV as I'm around 37-39 mph, and ...

2c) The FEH stays in EV longer at higher speeds. I can maintain the above high-30-mph for a short while, although it does require the lightest touch.

What 2 a-c all wrap-up to - as I tell my friends - is that "I can't keep the car from shutting off the ICE if wanted to."

3) My MPG this tank is noticeably higher on the NAV. After about 85 miles on this tank the NAV shows my MPG at 35.5 MPG ... though it still does fluctuate for periods of heavy accerlation (getting on the highway) and EV mode (on the side streets near home).

4) My "Miles to Empty" - when added to my Trip odometer for this tank - finally total greater than 450 miles "to empty." With 85 on the tank and an estimated 425 to empty, I am hoping to break 500 miles with this run.

I hope this helps some of the newer FEH owners by providing some things to look for. And for the veterans out there, is this the "breaking in" we've heard about? Or is there more to come (please say there's more to come!)? Thanks!

-Andrew

 

That... as far as I can tell... has MUCH more to do with the inaccuracy of the shutoff on the pump than any accuracy/inaccuracy of the NAV or your calculations. I have a ScanGuage. They tell you to calibrate it by pumping the tank full, resetting it, driving until the gas is pretty close to empty (1/4 tank or so) and then you check what the Scanguage says and what the pump says. You use the same pump for both fillups. You enter the % difference into the scanguage. Now I've done this NUMEROUS times at the same pump, on one clickoff of the pump. My % has ranged from -5% to nearly +10%. The accuracy one gets from the pump number just is NOT very good. They don't have some fancy shutoff mechanism, they just use back pressure and its not terribly accruate... doesn't need to be... it just keeps you from overfilling the tank. The amount of gas dispensed is pretty accurate but there is little guarantee the tank is exactly as full as it was the last time.

After alot of fiddling with the scanguage I've pretty much just looked for the most common reading and set the scanguage adjustment to +6%. and what do you know...my NAV usually agress with my scanguage to better than 1 MPG until its clear that the NAV has run past the end of its memory.

In short... I think the NAV is "fairly accurate" at least for my FEH and my driving style so I wouldn't put much stock into the differences between it and hand calculations--they just aren't very accurate until you average a BUNCH of them together over several tanks.

I will say.. that at around 2000-3000 miles I definitely noticed a bump up in my mileage, but I also bought mine in the winter.

 

Oh there's more to come. You'll continue to hone your skills, and as your tires wear down some you'll find improvement. Good luck with that 500 mile tank... it eluded me for about six months. But like TeeSter I bought mine when the weather was cooler.

 

I bought my baby (his name is Duke) on April 28. Today, I put the 8th tank of gas in. When I calculated my tank MPG, I got a lovely surprise: 34.5!!! This is my first above 33, so the fact that on this tank I became a hypermiler is really exciting to me. I hit 3000 miles just before this tank. I also have been doing more of the coasting in neutral, and just today increased my PSI to 40. I'm hoping to get in a 36 MPG tank in this summer (but, since we're having another flippin' heat wave with temps over 90, I think the AC may have to come on once or twice.).

 

Mike M, I am going to ask you respectfully not to refer to people as "clowns" If you don't agree with what some people do, by all means put in your 2 cents but calling people names is not how we go about it. I strongly disagree with how you feel about drafting, but you won't find me calling you a "clown" or anything else for that matter. Lets try to be a bit more mature here. what do you say?