The Low Gear Advantage
#51
10-14-2005, 08:23 PM
Re: The Low Gear Advantage
Hi Gary G:
___Can you try a few unorthodox pedal transients (fast/slow/multiple undulations into and out of) when entering ICE-Off from D to L for me? The Prius II and Insight had special accelerator tricks for nailing down Glide/Leanburn and NOx purge events respectively as efficiently as possible. I am wondering if there is a way to jump into EV/Glide in the Escape HEV with a quick shift to L from D at 40 mph and a few accelerator pedal manipulations to remove all hint of Regen before she goes ICE-Off? I hated that transition in the short < 1 hour I had behind the wheel of the Escape HEV in that type of lower speed condition and if there was a way to remove Regen with a multiple-movement Accelerator pedal angle both before/after the D to L shift and into ICE-Off, it may help smooth out that transition for another 1 to 2 + mpg over a segment or tank when applicable?
___Good Luck and thanks in advance.
___Wayne R. Gerdes
___Waynegerdes@earthlink.net
___Can you try a few unorthodox pedal transients (fast/slow/multiple undulations into and out of) when entering ICE-Off from D to L for me? The Prius II and Insight had special accelerator tricks for nailing down Glide/Leanburn and NOx purge events respectively as efficiently as possible. I am wondering if there is a way to jump into EV/Glide in the Escape HEV with a quick shift to L from D at 40 mph and a few accelerator pedal manipulations to remove all hint of Regen before she goes ICE-Off? I hated that transition in the short < 1 hour I had behind the wheel of the Escape HEV in that type of lower speed condition and if there was a way to remove Regen with a multiple-movement Accelerator pedal angle both before/after the D to L shift and into ICE-Off, it may help smooth out that transition for another 1 to 2 + mpg over a segment or tank when applicable?
___Good Luck and thanks in advance.
___Wayne R. Gerdes
___Waynegerdes@earthlink.net
#52
10-15-2005, 01:15 AM
Re: The Low Gear Advantage
There's a lot of experimentation going on here, and I think that's great. But I want to plant something in the back of your collective minds that I learned the hard way.
The engineers that built these vehicles may not have had the kind of constant pedal movement we're all playing with in mind when they chose the materials used in the electronic throttle/accelerator pedal system.
Before the FEH I owned a 2000 Volvo V70XC. This was one of Volvo's (remember Volvo is a member of Ford's Premeir Auto Group) cars to include electronic throttle control. At a little over 50K miles I had the joy of replacing the electronic throttle module at the cost of a little over $1000. A few thousand miles later I replaced the accelerator pedal (which I was able to do myself, unlike the throttle) as well. I am not the only Volvo owner to experience this.
The design of these components utilized simple, thick-film potentiometers to provide a resistance value to the computer, which is then used to determine the torque request of the driver. Problem is, over the course of several thousand miles, the metal contactor in the potentiometer wears against the thick-film resistor, and eventually wears through it.
Now it's possible that Ford has designed their ETM and accelerator pedals to use non-contacting parts, or that they're using a more durable resistance element if they did use a potentiometer. From the service manual I can't tell anything other than a reference to this being a "generation 2" eletronic throttle.
I do know that there have been a few "classic" Prius that have had to get new accelerator pedals as well.
The engineers that built these vehicles may not have had the kind of constant pedal movement we're all playing with in mind when they chose the materials used in the electronic throttle/accelerator pedal system.
Before the FEH I owned a 2000 Volvo V70XC. This was one of Volvo's (remember Volvo is a member of Ford's Premeir Auto Group) cars to include electronic throttle control. At a little over 50K miles I had the joy of replacing the electronic throttle module at the cost of a little over $1000. A few thousand miles later I replaced the accelerator pedal (which I was able to do myself, unlike the throttle) as well. I am not the only Volvo owner to experience this.
The design of these components utilized simple, thick-film potentiometers to provide a resistance value to the computer, which is then used to determine the torque request of the driver. Problem is, over the course of several thousand miles, the metal contactor in the potentiometer wears against the thick-film resistor, and eventually wears through it.
Now it's possible that Ford has designed their ETM and accelerator pedals to use non-contacting parts, or that they're using a more durable resistance element if they did use a potentiometer. From the service manual I can't tell anything other than a reference to this being a "generation 2" eletronic throttle.
I do know that there have been a few "classic" Prius that have had to get new accelerator pedals as well.
Last edited by stevewa; 10-15-2005 at 01:18 AM.
#53
10-15-2005, 09:02 AM
Re: The Low Gear Advantage
I just thought of something while driving yesterday...
The use of L, as we all know now, isn't some magic pill. It's just a different way of recovering the same amount of energy that you would by applying a bit of braking - as long as you don't brake hard enough to engage the friction brakes, in which case you would be giving up some of that energy to heat.
But I thought about another loss that gives L an advantage.... brake lights. When you're in a situation (heavy traffic, lots of stop & go) where L would be useful, you're brake lights would be using a lot more electricity in D than in L.
Maybe John has some ideas about how much might be lost to this use of brakes since he's done plenty of calculations/test of how much drain the taillights/brake lights use, and he's installed much more efficient LED versions. I'm just wondering if this may be a significant factor... and until I find out more, I've been using N when stopped on flat surfaces (and when the ICE is off, because no charging happens in N), rather than keeping those brake lights lit all the time.
The use of L, as we all know now, isn't some magic pill. It's just a different way of recovering the same amount of energy that you would by applying a bit of braking - as long as you don't brake hard enough to engage the friction brakes, in which case you would be giving up some of that energy to heat.
But I thought about another loss that gives L an advantage.... brake lights. When you're in a situation (heavy traffic, lots of stop & go) where L would be useful, you're brake lights would be using a lot more electricity in D than in L.
Maybe John has some ideas about how much might be lost to this use of brakes since he's done plenty of calculations/test of how much drain the taillights/brake lights use, and he's installed much more efficient LED versions. I'm just wondering if this may be a significant factor... and until I find out more, I've been using N when stopped on flat surfaces (and when the ICE is off, because no charging happens in N), rather than keeping those brake lights lit all the time.
#54
10-15-2005, 09:44 AM
Re: The Low Gear Advantage
Taking a look at a typical automotive bulb, it's 27 watts, so you're looking at about 54 watts for 2 brake lights. That's fairly insignificant when it comes to mileage, but I guess everything adds up in the end. Headlights are typically 55 watts each, or 35 watts each for HID headlights.
#55
10-15-2005, 01:14 PM
Re: The Low Gear Advantage
Add more to that since it's 3 brake lights.
Considering that the headlights consume about .9mpg . . . and that much of this brake light usage is at lower speeds where a constant load (such as lighting drain) has more of an impact on overall efficiency, I think it might be another thing just to keep in mind.
I mean just being aware of all these little things, and changing habits slightly here and there could mean a whole mpg or more gain. I know that I'm much more conservative with the fan than I used to be now that I know it sucks 1.3mpg on high.
I mean I'm not going to go sacrificing safety or comfort chasing after an extra fraction of a mpg, but when there are more efficient means to the same end it's an easy choice.
Considering that the headlights consume about .9mpg . . . and that much of this brake light usage is at lower speeds where a constant load (such as lighting drain) has more of an impact on overall efficiency, I think it might be another thing just to keep in mind.
I mean just being aware of all these little things, and changing habits slightly here and there could mean a whole mpg or more gain. I know that I'm much more conservative with the fan than I used to be now that I know it sucks 1.3mpg on high.
I mean I'm not going to go sacrificing safety or comfort chasing after an extra fraction of a mpg, but when there are more efficient means to the same end it's an easy choice.
#56
10-15-2005, 06:35 PM
Re: The Low Gear Advantage
I have no idea what your looking for Wayne. This P and G thing is not part of my getting the best MPG out of the FEH I have yet. If there is more MPG I can get, please explain further. Playing with my FEH without knowing what your looking for may damage systems like Steve has said. I don't read about the Prius or Honda. You have a better view of this I admit but explain it here. I have a son at MIT to help me that needs my cash and will help me understand. Your not connecting here.
Gary
Gary
#57
10-16-2005, 08:48 AM
Re: The Low Gear Advantage
Hi GaryG:
___I was not looking for a pure P&G as your Escape HEV is not really designed or setup for it properly. I only saw fleeting seconds per minute of pure Glide in my short time behind the windscreen of John’s? I am positive this will be completely allowed in Gen-II … hopefully? What I would like you to look for is a method of entering ICE-Off - EV/Glide in L from ICE-On in D at 40 mph or less without any regen appearing and an absolutely smooth transition being the result. Another 2 or 3 - 2mm cycles of the accelerator pedal is not going to damage the DBW setup or you would have those driving all city environments, DBW system failing far more frequently then those driving mostly highway. Ford’s DBW setup is one of their most robustly designed systems they have ever placed in an automobile.
___Look for a method of cycling the accelerator ever so slightly in/out or out/in during the transition from ICE-On to ICE-Off in L so that you can achieve ICE-Off without any regen appearing and with an absolutely seamless transition. Think of how smooth your coast down is while in D from 40 + mph all the way to a stop without regen. Your ICE does not shut down and you have very little to no Regen appearing but it is almost seamless! You want this same transition feel but with ICE-Off to occur. I am not saying there is a magic pedal tap that can accomplish this but at least attempt to optimize the ICE-On to ICE-Off transition in L with just a few slight pedal movements is what I would be looking for.
___Does that help?
___Good Luck
___Wayne R. Gerdes
___Waynegerdes@earthlink.net
___I was not looking for a pure P&G as your Escape HEV is not really designed or setup for it properly. I only saw fleeting seconds per minute of pure Glide in my short time behind the windscreen of John’s? I am positive this will be completely allowed in Gen-II … hopefully? What I would like you to look for is a method of entering ICE-Off - EV/Glide in L from ICE-On in D at 40 mph or less without any regen appearing and an absolutely smooth transition being the result. Another 2 or 3 - 2mm cycles of the accelerator pedal is not going to damage the DBW setup or you would have those driving all city environments, DBW system failing far more frequently then those driving mostly highway. Ford’s DBW setup is one of their most robustly designed systems they have ever placed in an automobile.
___Look for a method of cycling the accelerator ever so slightly in/out or out/in during the transition from ICE-On to ICE-Off in L so that you can achieve ICE-Off without any regen appearing and with an absolutely seamless transition. Think of how smooth your coast down is while in D from 40 + mph all the way to a stop without regen. Your ICE does not shut down and you have very little to no Regen appearing but it is almost seamless! You want this same transition feel but with ICE-Off to occur. I am not saying there is a magic pedal tap that can accomplish this but at least attempt to optimize the ICE-On to ICE-Off transition in L with just a few slight pedal movements is what I would be looking for.
___Does that help?
___Good Luck
___Wayne R. Gerdes
___Waynegerdes@earthlink.net
#58
10-16-2005, 11:59 AM
Re: The Low Gear Advantage
Wayne, I go into EV so much it is petty much automatic what I do. At 40mph when I have a full battery, I have to be carefull to get the ICE off without starting it back again because of overcharge. I never had this problem using the tap brake method but with "L", I have to get out as soon as I can for coasting. If my foot has any presure on the gas pedal during the shift to "L", the ICE will not shut down for me.
Here is what I do at all speeds using "L" for coast. I keep the energy screen on most of the time so this is what I see. I shift to low and the generator arrow starts to point to the battery. As soon as I see the tach drop down to 1,000 RPM's and bounce I shift to "D" before the tach even drops. I know this is the split second the computer has made its decisions to turn off the ICE, but the engine is still turning at this point. As soon as I move to "D" all the arrows go out on the energy screen even if the engine is still turning. Once the computer sends the message and the tach starts to make a movement I go into coast with no regen and the arrows all go out before the tach drops. Using the gas pedal after this just causes the battery to point to the drive axle as a battery drain.
Now after I have coasted to my desired speed with no regen happening to this point, I apply the gas pedal for EV under 35mph. After the pedal movement down starts, then I will start to see the regen arrow come back when I let off the pedal in EV sometimes.
I assumed I was in what you call "Glide" till I start any movement of the gas pedal. This is where you lose me. Any "Pulse" or movement of the gas pedal will interupt the glide with the regen arrow coming on in EV. If I do not touch the brake or gas pedal, the energy screen has no arrows pointing anywhere, everything is shut off till I start touching the pedals.
Did you find something differant when you drove the FEH? The Prius and Insight must be set up differant or I'm missing something. Please explain if I am. I'll try to get you answers if I can.
Gary
Here is what I do at all speeds using "L" for coast. I keep the energy screen on most of the time so this is what I see. I shift to low and the generator arrow starts to point to the battery. As soon as I see the tach drop down to 1,000 RPM's and bounce I shift to "D" before the tach even drops. I know this is the split second the computer has made its decisions to turn off the ICE, but the engine is still turning at this point. As soon as I move to "D" all the arrows go out on the energy screen even if the engine is still turning. Once the computer sends the message and the tach starts to make a movement I go into coast with no regen and the arrows all go out before the tach drops. Using the gas pedal after this just causes the battery to point to the drive axle as a battery drain.
Now after I have coasted to my desired speed with no regen happening to this point, I apply the gas pedal for EV under 35mph. After the pedal movement down starts, then I will start to see the regen arrow come back when I let off the pedal in EV sometimes.
I assumed I was in what you call "Glide" till I start any movement of the gas pedal. This is where you lose me. Any "Pulse" or movement of the gas pedal will interupt the glide with the regen arrow coming on in EV. If I do not touch the brake or gas pedal, the energy screen has no arrows pointing anywhere, everything is shut off till I start touching the pedals.
Did you find something differant when you drove the FEH? The Prius and Insight must be set up differant or I'm missing something. Please explain if I am. I'll try to get you answers if I can.
Gary
#59
10-16-2005, 01:45 PM
Re: The Low Gear Advantage
Hi Gary G:
___Now you are talking! Why haven’t you posted this level of detail before or maybe I just missed it? For the ICE-Off condition without regen, you shift to L at ~ 40 mph and as soon as you see the tach bounce off of 1K RPM, you shift back to D for the perfect Glide/coast or EV mode w/ ICE-Off? That sounds perfect! I have seen the tach bounce just before ICE-Off but I could not achieve ICE-Off with the shift to L without some regen taking a mile or two/hour away. I tried the double tap of the brakes in D one time but it did not allow the Escape HEV to go ICE-Off and I didn’t have the time to play around …
___Once in EV w/ ICE-Off, I would slowly bleed off speed with small amounts of EV and small amounts of Glide (no-arrows anywhere to the best of my ability) until a particular low speed target was reached. I would hold that low speed target in EV until the ICE started up again for whatever reason. As for the Pulse, that happens way later at the end of the technique. If the ICE starts up because of the difference engine between the pre/post O2 CAT sensors triggering an emissions restart, low SoC, low coolant temp, low AIT, you self induced ICE-On because of traffic or whatever, get on the accelerator until you are back up to 40 + mph again. Your SoC will have dropped to a much lower level by the second Glide/EV but it doesn’t matter as it is the sustainability afterwards that counts. This is exactly where the 60.0 + mpg is going to come from whenever you can maintain a < 40 mph speed band while driving around town.
___The Prius II only needs a heavy let off of the accelerator and slight reapplication to get into a pure ICE-Off Glide w/ little to no regen. The Insight does not have an EV or Glide mode but does have a straight up AS below 20 mph. The Insight’s fancy footwork was helpful between NOx purge and Lean-Burn events with a slight let off, reapplication, let off again during a NOx purge event and a slight let off with very slow reapplication to get into lean-burn most efficiently while still at speed. Tbaleno’s CVT based HCH was unusual in that I never did feel a NOx purge event or any type of slight slow down when it achieved Lean-burn. I saw the normal jump of the Instantaneous to ~ 80 mpg once leanburn was evoked but I never felt any hesitation or acceleration in the HCH. I want to add that just like the Prius II, the Escape HEV’s low speed band really doesn’t matter. If you had to slow to 15 mph, 20 mph, or even 33 mph on the low side, a P&G afterwards to another varying band will still get you to your magic 60 + mpg.
___Please post your exacting D to L to D to ICE-Off and EV/Glide details as you have described them here in the other Escape Forums because it sounds better then what I was using in the less then an hour I was able to play with the 2WD Escape HEV in a rural/city environment. Both you and I know who will post about this being their exacting method and how it makes them the better driver etc. but it will be for the betterment of all Escape HEV drivers if they know how you are performing the transition with little in the way of the slight Regen-induced slow down hit …
___Thank you for following up again and again as some of us are more thickheaded then others is all
___Finally, has any other Escape HEV pilot that you know of connected up a scan gauge w/ a FE readout to their Escape HEV? I would really like to know what she is actually worth in an all-city like environment with maximum P&G applied. Just like the Prius II in the marathon attempt, pegging out the Ford OEM FCD’s just leads you to 60.0 and 99.9 mpg in the Prius II. Without the special metric MFD supplied by our friend Ken1784, we would have had to be content with just 99.9 mpg readouts throughout the entire event knowing full well we were receiving even more. It is definitely a good time to be alive if you are a FE enthusiast like I am
___Good Luck
___Wayne R. Gerdes
___Waynegerdes@earthlink.net
___Now you are talking! Why haven’t you posted this level of detail before or maybe I just missed it? For the ICE-Off condition without regen, you shift to L at ~ 40 mph and as soon as you see the tach bounce off of 1K RPM, you shift back to D for the perfect Glide/coast or EV mode w/ ICE-Off? That sounds perfect! I have seen the tach bounce just before ICE-Off but I could not achieve ICE-Off with the shift to L without some regen taking a mile or two/hour away. I tried the double tap of the brakes in D one time but it did not allow the Escape HEV to go ICE-Off and I didn’t have the time to play around …
___Once in EV w/ ICE-Off, I would slowly bleed off speed with small amounts of EV and small amounts of Glide (no-arrows anywhere to the best of my ability) until a particular low speed target was reached. I would hold that low speed target in EV until the ICE started up again for whatever reason. As for the Pulse, that happens way later at the end of the technique. If the ICE starts up because of the difference engine between the pre/post O2 CAT sensors triggering an emissions restart, low SoC, low coolant temp, low AIT, you self induced ICE-On because of traffic or whatever, get on the accelerator until you are back up to 40 + mph again. Your SoC will have dropped to a much lower level by the second Glide/EV but it doesn’t matter as it is the sustainability afterwards that counts. This is exactly where the 60.0 + mpg is going to come from whenever you can maintain a < 40 mph speed band while driving around town.
___The Prius II only needs a heavy let off of the accelerator and slight reapplication to get into a pure ICE-Off Glide w/ little to no regen. The Insight does not have an EV or Glide mode but does have a straight up AS below 20 mph. The Insight’s fancy footwork was helpful between NOx purge and Lean-Burn events with a slight let off, reapplication, let off again during a NOx purge event and a slight let off with very slow reapplication to get into lean-burn most efficiently while still at speed. Tbaleno’s CVT based HCH was unusual in that I never did feel a NOx purge event or any type of slight slow down when it achieved Lean-burn. I saw the normal jump of the Instantaneous to ~ 80 mpg once leanburn was evoked but I never felt any hesitation or acceleration in the HCH. I want to add that just like the Prius II, the Escape HEV’s low speed band really doesn’t matter. If you had to slow to 15 mph, 20 mph, or even 33 mph on the low side, a P&G afterwards to another varying band will still get you to your magic 60 + mpg.
___Please post your exacting D to L to D to ICE-Off and EV/Glide details as you have described them here in the other Escape Forums because it sounds better then what I was using in the less then an hour I was able to play with the 2WD Escape HEV in a rural/city environment. Both you and I know who will post about this being their exacting method and how it makes them the better driver etc. but it will be for the betterment of all Escape HEV drivers if they know how you are performing the transition with little in the way of the slight Regen-induced slow down hit …
___Thank you for following up again and again as some of us are more thickheaded then others is all
___Finally, has any other Escape HEV pilot that you know of connected up a scan gauge w/ a FE readout to their Escape HEV? I would really like to know what she is actually worth in an all-city like environment with maximum P&G applied. Just like the Prius II in the marathon attempt, pegging out the Ford OEM FCD’s just leads you to 60.0 and 99.9 mpg in the Prius II. Without the special metric MFD supplied by our friend Ken1784, we would have had to be content with just 99.9 mpg readouts throughout the entire event knowing full well we were receiving even more. It is definitely a good time to be alive if you are a FE enthusiast like I am
___Good Luck
___Wayne R. Gerdes
___Waynegerdes@earthlink.net
Last edited by xcel; 10-16-2005 at 01:49 PM.
#60
10-16-2005, 05:37 PM
Re: The Low Gear Advantage
Wayne, no this is the first I have I posted about this. The only reason I started doing this was because I pack my battery more than I ever have since I started this thread. Ray and Privus Prime posted about using "L" which I incorporated in my driving style. With all the EV driving I do, I seen this as a major breakthrough in my FE (fuel efficiency) by charging the battery when I need to. It started becoming a problem when the ICE would start back up do to an overcharge. I started shifting back to "D" as early as I could so the battery would stop charging. I found out when I saw the RPM's show signs of ICE off, I could go to "D" and ICE still continued to shut off. The move to "D" would stop the green arrows and I knew the ICE was not going to start back up again unless it was to late and the computer started the ICE back up to burn off the overcharge. I knew I was getting a better coast without any energy flow from the computer screen. And yes, most of time I can increase my speed to 32-38mph in EV and let off slowly without regen kicking back on so I can glide again with no arrows. Its a toss up because I'm in EV charging the battery from the wheels which give me even more time in EV but it also slows me down. I can always shift to "L" and get regen when I need it. Keeping control of the computer's actions is what's needed because the computer doesn't know the road ahead like we do.
You were confusing me with the gas pedal movement during this process because as you see, I don't touch it till I need to maintain my speed in EV. I reread your posts and found I've already been doing what you were asking me to try for you for other reasons (overcharge). The term Pulse and Glide was confusing me but I have a better understanding now thanks to you. Basicly I've been using it all along by tapping the brakes in the past 7 months. I'm thinking that you were to close to 40mph when you tried it and you need to get it just right at that speed. You still need to know just when to make that shift back to "D" from "L" but I think most here can get that down ok.
The scan guage w/ a FE readout is over my head and I've only seen three other FEH's in my area as they went by. As you know, I can't get MPG readings over 60 which holds me back as I try things. I think Ford under estimated us with that guage.
As far as me reposting the information on other sites, feel free to cut and paste any of my posts. My wife has got a lot of honey do's that are backing up here. Anyway, it was your efforts that brought this to surface, not mine.
Gary
You were confusing me with the gas pedal movement during this process because as you see, I don't touch it till I need to maintain my speed in EV. I reread your posts and found I've already been doing what you were asking me to try for you for other reasons (overcharge). The term Pulse and Glide was confusing me but I have a better understanding now thanks to you. Basicly I've been using it all along by tapping the brakes in the past 7 months. I'm thinking that you were to close to 40mph when you tried it and you need to get it just right at that speed. You still need to know just when to make that shift back to "D" from "L" but I think most here can get that down ok.
The scan guage w/ a FE readout is over my head and I've only seen three other FEH's in my area as they went by. As you know, I can't get MPG readings over 60 which holds me back as I try things. I think Ford under estimated us with that guage.
As far as me reposting the information on other sites, feel free to cut and paste any of my posts. My wife has got a lot of honey do's that are backing up here. Anyway, it was your efforts that brought this to surface, not mine.
Gary
