'09 FEH Techniques
 

After 10 months and 11,000 miles with my '09 FEH I thought I'd share some easy techniques I'm using. I have two SGII's in my FEH and monitor SoC , Instant MPG , LP and LOD on one and Tank MPG on the other most of the time.

By monitoring SoC % I know when to go EV and when to restart the ICE with the blip of the accelerator pedal. On flat roads I use cruise controlhttp://images.intellitxt.com/ast/adT...lass_10x10.gif to get the best MPG under 50mph. If possible, I shift to "N" at about 40.8% SoC for a glide as the Hv battery drops near a restart (40.1-40.4%) and then shift back to "D" for the blip restart. The blip restart prevents an automatic restart that causes a big drop in the SoC . Shifting to "N" cancels Cc and provides the longest glide with a slower drop in speed. P&G works best for me with 35mph on the high side and 25mph on the low side.

I've found that pulsing up to speed at 80% engine LOD and letting the Cc maintain speed while SoC builds is the best. The Instant MPG is much better in Cc than I can maintain and it's not uncommon to see an Instant 30-45mpg while the ICE and generator bring up a 40.8% SoC . In general the best Instant MPG while under heavy charging is above 30mph and below 45mph. When I'm above 32mpg Instant MPG while charging in Cc I will let the ICE continue to charge the battery for a longer EV segment. This is when for some reason the ICE still is running and not dropping into EV mode in Cc . It could be due to a slight up-grade slope or a headwind but I take advantage of the good MPG while charging the low battery.

I monitor LOD for acceleration and climbing large bridges. Climbing bridges I try to maintain or slightly decrease speed while maintaining RPM between 1,500 - 1,800 and LOD less than 88%. I go EV at the top and shift to "N" to increase speed to 40mph on the way down and hold 40mph with "D" and light regen with the brake pedal to build SoC . At the bottom of the bridge at 40mph I shift back to "N" to a point I need to maintain speed in EV with CC.

I monitor LP (Open/Close Loop) for fuel-cut. Open Loop and a 9,999mpg Instant MPG reading on the Sgii means I'm getting full fuel-cut. Under 40mph the '09 will go 100% fuel-cut during decel in "L" but it's rare that I use that because of better regen by using the brake pedal.

I monitor Tank MPG to not lose control of my tank goal. Highway driving lowers tank MPG so this helps me limit just how much highway driving I should do to meet my tank goal.

Let us know what works and does not work for you!

GaryG

Re: '09 FEH Techniques
 

What do you have the SG fuel cut setting set to?

Have you found it to be different than the 2005-2008's?

Re: '09 FEH Techniques
 

I went from the default setting to 17 at the same time I was raising fuel calibration at every tank refill. At one point at about a 12 fuel calibration I started to just lower fuel-cut to see if it was making a difference. I went all the way down to a fuel-cut setting of 6 where it is now and it did not lower the MPG to where it needed to be at 4% below the Nav tank reading at fill-up. At that point I began increasing fuel calibration again at fill-up till I got the SGII tank reading to match 4% below the Nav tank with a 14.2 fuel calibration. I'm near the end of this tank so at fill-up I'll change fuel-cut from 6 to 16 and see if it makes a difference in this next tank. I only make changes to the settings after a complete tank of gas of about 700 miles. If I find that the SGII has changed to a higher MPG compared to the Nav tank and pumped gas amount, I will begin to lower fuel-cut slowly again.

I did not have fuel-cut in my '05 enough to worry about changing the default setting of 24. The '09 has aggressive DFSO above 40mph in "D" and below 40mph in "L". In "L", you always get engine run-up and DFSO at the same time any time you let Off the gas pedal. In the '05 you only get engine run-up when the battery can't take the charge.

GaryG

Re: '09 FEH Techniques
 

The fuel cut-off setting should not be a guess.
It should not be by trial and error.
It should be the same for every car of the same model year.

All you need to do is monitor TPS Throttle Position Setting when you are in EV mode. This is the number you set your fuel cut-off value to. Either that, or the EV value +1.

That's it. There is a definate, deliberate way to set this.
You set it once, and you never change it again.
There is no "experimenting" required.

Hope that helps.
-John

Re: '09 FEH Techniques
 

Sorry John

Nothing I can remember from you has ever helped anything I can think of for my MPG. Now CarlD (desertdog), is the man for the SGII, not you. If he agrees with you OK, but this is a new '09 FEH and not a '05 FEH I'm talking about.

GaryG

Re: '09 FEH Techniques
 

Gary- It works the same way no matter the year, no matter if it is Ford, Toyota, or Honda ( or other )!!!

Did you even read the directions??? ( I guess not.... :( )

LOL!:D

Re: '09 FEH Techniques
 

I've read the section on CutOff in the SG-II manual. It states comparing Open/Closed Loop to the TPS position which might show "0". It explains Open Loop as bing when the engine is cold or at full throttle which I already knew. It states that some engines cut fuel while coasting. Okay, I see that but Open/Closed Loop is wether or not the PCM is using sensor inputs to control injector pulse width. That's not going to tell you squat about fuel usage!

Re: '09 FEH Techniques
 

Fuel cut is open loop operation by definition. Open loop does not mean only warm-up or WOT - fuel enrichment can and does happen at less than WOT and a warm engine. The SG fuel cutoff parameter is the TPS setting at which anything below this combined with open loop will result in no fuel usage assumed by the SG. If you set it to the EV TPS reading like John suggested you will never see fuel cut. The EV TPS in my 2005 is 12 and I have seen 11 in a 2006. All that being said true fuel cut in my 2005 is very uncommon. I figured out the bus message (not PID) that the PCM sends to the IC that indicates fuel flow and it doesn't go to zero that I can see except for ICE spin up when MxC is decreasing or zero.

Re: '09 FEH Techniques
 

That's true, but you get a 9,999mpg Instant MPG reading also to confirm fuel-cut.

GaryG

Re: '09 FEH Techniques
 

Yep, that's mentioned also but I don't know why Open/Closed Loop is even mentioned!