Software Updates from Ford to improve MPGs

[MaineFusion]

Thanks everyone for your replies, I am new at this posting thing. I do have two more comments, I have read many posts and most say they are getting less than 40 miles on the highway, so how can Ford say 47 City and 47 highway? Is the fusion included in the Ford settlement? Second, There seems to be a chance that if I get the software updated again (being it's good they didn't do it right the first time) that my MPG will go down.

 

I've averaged over 50mpg for at least the past 8,000 miles. When driving to and from work (47mi each way) I typically average between 49 - 54 mpg. Most of this commute is at highway speeds. I do set my max speed to 63 mph. If I were to set my max speed to 65mph, I'd lose around 2mpg. The max speed difference between 63 and 65mph would only save me a couple minutes each way, so I really don't care about gong faster. If I were to drive 70mph, I'd probably cut my fuel economy by at least 7 mpg.

 

When driving country roads with 35-45 mph speed limits I can reliably do around 63 mpg.

 

What fuel economy you get is all about driving style and how much extra weight you are hauling around. It isn't just about how fast you drive but how well you listen to the car. I can squeeze out extra EV miles by simply listening to the engine and knowing how hard to accelerate under which conditions. In city driving where there are lots of traffic lights I will accelerate slower and try to stay in EV mode as long as possible. If accelerating to highway speeds I'll try to stay in EV mode to around 20-30mph and then accelerate harder to push the ICE engine to two bars to get maximum efficiency out of it. I also routinely keep an average braking score of 99%. It would be 100% if it weren't for the stray traffic light that catches me short.

[jsolan]

I posted this in another thread before I realized the current conversation in this thread.

The past 3 trips I've had at 68-70 mph I have not been able to crack 40 mpg. Right now I feel like I lost 1.5-2 mpg at those speeds since the software update. I don't do enough highway driving to really concern myself with 2 mpg, but I'm starting to think the update actually hurt my vehicle at highway speeds. I'm still getting 43-45 overall and 48+ in ideal conditions so I'm not dis-satisfied. Even prior to the update I could only get 41 at 68 mph. I'm amazed people driving near 65 are able to get 45 mpg on flat roads. Once at cruising speed, there's nothing I can think of that a driver can do differently (aside from PnG) that would explain a difference because of driving style.

While initially after the update my short trips (under 3 miles) seemed to be better (high 30's or better), they've recently tanked as well. I'm getting as low as 18 mpg on trips to the store (1.5 miles away). Again I'm not concerned because the overall average tends to balance out since these trips are only once or twice a week.

[VNLongBeach]

Ok I understand driving at slower speeds and using the brakes will give high MPGs because the battering charging and all, but the speed limit on highways is 70 and in some areas 75. You can't drive at 55. Is the EPA and Ford testing cars at 55 to determine the MPGs? I avoid the highways within town just to keep the speed low and get the MPGs, but when you are going 200 to 300 miles I don't want to be taking the side roads. At 70 the car should give a reasonable amount say 45 mpgs not something in the 30s when the sticker shows 47. Based on the engine size shouldn't the ICE average mid 30s and with the EV add a few more to get it onto the mid to low 40s

[Eddie Sessum]

Ok I understand driving at slower speeds and using the brakes will give high MPGs because the battering charging and all, but the speed limit on highways is 70 and in some areas 75. You can't drive at 55. Is the EPA and Ford testing cars at 55 to determine the MPGs? I avoid the highways within town just to keep the speed low and get the MPGs, but when you are going 200 to 300 miles I don't want to be taking the side roads. At 70 the car should give a reasonable amount say 45 mpgs not something in the 30s when the sticker shows 47. Based on the engine size shouldn't the ICE average mid 30s and with the EV add a few more to get it onto the mid to low 40s

 

 

But on the highway you don't use the brakes. So your not getting regen. Your just making the ICE work harder and use more fuel to recharge the battery to go into EV mode again. No gas to electric system is 100% efficient and id say the ICE charging system is around 75% efficient so your loosing 25% of your efficiency by going back and forth. I know my 75% number isnt accurate but its an example.

 

Its why hybrids do so well in the city mpg and traffic. That stopping and charging off the brakes makes it go way up but you have very little to none of that on the highway.

 

Its why you dont see electric cars that run completely on a generator without a battery. Without regen its a waste to put those systems. (Nobody start comparing this to trains and there diesel electric setups plz).

[dkegel]

 

... No gas to electric system is 100% efficient and id say the ICE charging system is around 75% efficient so your loosing 25% of your efficiency by going back and forth. I know my 75% number isnt accurate but its an example.

 

 

Yes, but you gain back way more than that 25% when you drive a mile or so (as an example) with no ICE at all. If you're trying to make the point that the overall MPG will be higher if EV mode never kicks in on the highway, I don't buy it.

 

Dave

[Eddie Sessum]

You have had people explain the same to you on other posts and you refuse to believe it.. Im not trying to convince you anything anymore. EV power has to come from somewhere, it doesnt just pull it out of the air.

[dkegel]

I understand it has to come from somewhere. But how can you say that getting something like 100mpg in EV mode doesn't make up for the couple MPG that is lost when charging the battery? No one has explained that to me.

 

Dave

[Eddie Sessum]

Look at how many miles of 20ish takes to recharge at those speeds. Compare that and divide to how many ev miles you get on one charge before it kicks on the ice. You don't get me distance on full ev at hwy speeds.

[milleron]

I don't believe that. Do you have any data to back that up or is it theory? I am think the ICE running at 65 mph is going to use the same amount of fuel weather it's charging the battery or not. And even if it were to use a tiny bit more fuel, that has to be more than offset by traveling 65 mph without the ICE.

 

Dave

It's neither a matter of theory nor data. Eddie's statement has been accepted since the advent of mechanical engines. It's as simple as the fact that the more work a motor or engine has to do in a given amount of time, the more energy, gasoline in this case, will be required.

Remember that this car uses a continuously variable transmission. When it has to supply enough power to propel the car at 65 mph AND run the HVB generator, the injectors will input MORE fuel to develop the extra power and/or the car will run in a lower gear ration at higher ICE RPMs than when it's traveling at 65 mph without engaging the charging motor/generator. That's why the instantaneous mileage figure frequently hovers just above 20 mpg when the ICE starts to recharge a depleted HVB at highway speeds. When the HVB has completed charging, and the charging motor is no longer engaged, much less fuel is used, approximately HALF as much, and the instantaneous mpg figure gradually rises up to 40-43 mpg (in my FFH, at least), all while going exactly the same speed. So almost nothing could be further from the truth than the statement that an ICE uses the same amount of fuel at the same speed regardless of the load on it. If that were true, one would get the same mileage going up a 5% grade at 65 mph as going down it at 65 mph, which we all know is NOT the case.

[dkegel]

Yes. Not only did I have some terrible typos and spelling (really? weather?), I was wrong about the amount of fuel used. I was not thinking clearly. However, I have to believe that the extra fuel used to charge the battery is more than offset by periods of ICE free highway driving. I would be very surprised if Ford didn't have clear data proving the benefit before making that change to the software. But who knows?

 

Dave.

[Eddie Sessum]

Yes. Not only did I have some terrible typos and spelling (really? weather?), I was wrong about the amount of fuel used. I was not thinking clearly. However, I have to believe that the extra fuel used to charge the battery is more than offset by periods of ICE free highway driving. I would be very surprised if Ford didn't have clear data proving the benefit before making that change to the software. But who knows?

 

Dave.

 

 

Like i said before. On flat land the 62mph was the limit for best milage going back and forth and I believe it offset itself to a 0% gain.

 

In the hills, above 62mph is of big benefit because of downhill regen. Thats why some people can get over 50mpg average at 70-75mph. Just depends on the hilly layout.

[jeff_h]

However, I have to believe that the extra fuel used to charge the battery is more than offset by periods of ICE free highway driving.

 

This is what I was getting at in the other thread when I posted the basic graph that is based on the numbers on the spreadsheet -- I think that the slower speeds with the more EV periods yield a bit better MPG, while others will maintain that keeping a steady higher speed with the ICE running at a lighter load does the more efficient job. I've always said take a repeatable course (like the daily commute) and sample with various speeds... I've done that and found that the steady slower speed where the EV kicks in more tends to do better for my particular course/terrain, but that might not hold true for everyone's, which is why the term 'YMMV' exists.

 

http://fordfusionhybridforum.com/topic/7404-a-hypothesis-75mph-is-the-highway-mpg-sweet-spot/page-3

[Skydogz]

I just took a short trip yesterday using Cruise Control and in moderately heavy traffic and achieved 48 mpg!

I drove with CC set at 65mph. Got 43mpg coming back with CC set at 70mph.

 

Edited October 5, 2013 by Skydogz

[Eddie Sessum]

I just took a short trip yesterday using Cruise Control and in moderately heavy traffic and achieved 48 mpg!

I drove with CC set at 65mph. Got 43mpg coming back with CC set at 70mph.

 

 

Traffic def helps if you have ACC and it does autobraking and eco take-offs.

[Fastronaut]

I just got 45 MPG on a short round trip (12 Miles) including a long up hill stretch. Used ACC in ECO Mode with A/C set at 73.

[ROB281]

Using eco cruise both ways set to 68 on a 32 mile trip this tonight, and pulled 36.2, and 35.8 mpg

[Skydogz]

 

Traffic def helps if you have ACC and it does autobraking and eco take-offs.

I just realized that on the first leg of my round trip I got 48 at 65mph, but the round trip AVERAGE went down to 43 at 70mph. So I really got about 38mpg with 70mph set on CC on the return leg!

Edited October 6, 2013 by Skydogz

[hybridbear]

That makes no sense. Anytime the ICE is not running, that's a good thing.

 

Dave

Yes & no. See Eddie's comment below.

 

But using the ice to charge the battery uses more gas than the savings of keeping the ice on at high speed.. In the city the ev gains are from regen braking

An ICE turns a certain % of the energy contained in the gasoline into kinetic energy. Our ICE can also turn the gasoline energy into electrical energy by using the ICE to spin a generator. A certain % of the energy is lost because the generator is not 100% efficient. Another certain % will be lost when the energy comes back out of the battery because the electric motor isn't 100% efficient. As in Jeff's spreadsheet posted elsewhere there is the potential for the car to be more efficient with the ICE only in certain scenarios. This is why I'd like to get BSFC information for our ICE.

 

I think it makes a lot of difference, and to illustrate this -

 

Picture a portable generator that you have for power outages... start it up and let it run with no load and the tank will last (let's say) 6 hours... plug in a decent load and hear the engine change tone since it is now powering the electrical generator to provide output to the portable outlets, and the tank of gas will now last (let's say) 4-5 hours since the engine has more of a load on it.

 

Same concept with the FFH, as the ICE would use more fuel to generate electricity back to the battery than when not doing so.

Yes. Not only did I have some terrible typos and spelling (really? weather?), I was wrong about the amount of fuel used. I was not thinking clearly. However, I have to believe that the extra fuel used to charge the battery is more than offset by periods of ICE free highway driving. I would be very surprised if Ford didn't have clear data proving the benefit before making that change to the software. But who knows?

 

Dave.

Here's my thoughts... our ICE seems to like high loads. Unlike Toyota's HSD, the Ford system pretty much always loads up the ICE with a heavy generator load. In this post I explained about what I've seen with my ScanGauge relating to load and power output of the ICE. The Toyota Prius BSFC graph shows that the Prius can operate very efficiently at a much lower power demand. This means that it's more efficient for the Prius to rarely turn off the ICE except under very low power demand situations. However, the FFH seems to be more efficient at higher power demands.

 

Before the PCM Update the car would stay ICE only above 62 MPH. This meant that the ICE was heavily loaded at first to charge the HVB. Once the HVB reached a high SOC then the ICE would operate with a low power demand. At this low power demand the instant MPG would show 40+ typically, this was known as "ICE High" mode. When going downhill the ICE would continue to spin but the fuel injectors would shut off in what's known as DFSO (Decel Fuel Shut Off). However, the ICE was still consuming some of the gravitational energy of the descent to overcome internal friction. Now the ICE can shut off completely in these situations. I'm guessing that the PCM Update reason was that in ICE High the ICE isn't operating in its most fuel efficient BSFC range. The power demand is likely too low for our larger ICE to be efficient. The smaller 1.8L ICE in the Prius is still in its optimal BSFC range at lower power demands so it doesn't face this issue. Now the car will go into EV Mode and use down the battery. Then when the ICE comes on it will operate under a high load to recharge the battery and, in theory, operate in its most efficient BSFC range.

 

The complication is that charging isn't 100% efficient. It's possible that after the PCM Update the load to charge the battery combined with your driving conditions can push the ICE out of its most efficient BSFC range to the right, meaning that the power demand is too high. Before the update in ICE High mode this wouldn't happen. It's possible that in certain scenarios the charging losses of going in and out of EV Mode consume more energy than the energy wasted by operating in a less efficient BSFC zone in ICE High mode before the update.

[elle]

Hi everyone! I finally got the upgrade over the past weekend, and will be reporting on it over the next few weeks as things settle in. I'd stopped hypermiling after a while because it was just too intense and too much work for little gain. Driving like my normal manic self I was at about 38.5mpg lifetime average. This morning I hypermiled in to work to see what I could do and ended up at about 45mpg. That's not bad, but it's not outside the realm of what I was doing on that trip previously, so we'll see. I've reset my lifetime averages though, so hopefully that will improve.

 

One thing I am very happy about, knock on wood, is that the bluetooth streaming audio seems to be functioning properly.

 

Good to see everyone.

[DeeCee]

Hi everyone! I finally got the upgrade over the past weekend, and will be reporting on it over the next few weeks as things settle in. I'd stopped hypermiling after a while because it was just too intense and too much work for little gain. Driving like my normal manic self I was at about 38.5mpg lifetime average. This morning I hypermiled in to work to see what I could do and ended up at about 45mpg. That's not bad, but it's not outside the realm of what I was doing on that trip previously, so we'll see. I've reset my lifetime averages though, so hopefully that will improve.

 

One thing I am very happy about, knock on wood, is that the bluetooth streaming audio seems to be functioning properly.

 

Good to see everyone.

Good to hear from you!

[gotrojans]

Ever since this TSB was applied, my gas mileage has been worse. I take it in for the first oil change today, and I mention the TSB and worse gas mileage. The service rep agreed and acknowledged that Ford knows about.

 

No ETA on fix and the TSB can't be removed.

 

Does anyone know of the ETA for the patch for this TSB?

 

Thanks

 

Ron

[dkegel]

I doubt there is a patch coming and I don't think Ford believes there is any issue. I think your service rep was just telling you what you wanted to hear. Most people have been fine after the upgrade.

 

Dave

[smr2112]

I think the unspoken consensus on the MPG TSB is that overall, it makes very little difference really either way.

At least that's my feeling.

 

And if you're new to owning a hybrid and wherever you live, it's gotten 10,20,30 degrees colder in the

past few weeks, you're mileage will go down. Don't expect that through the winter you're going to get

the same as you did during the summer. I'd think that would be very obvious to most, but I doubt

it is to some.

 

My 2010 FFH went down at least 5-6 MPG in the coldest part of the winter and there isn't much that

can be done about it.

[dkegel]

Good point on the weather change. It's definitely a factor. Spring and fall are the ideal times. No heat or AC makes for nice MPG numbers.

 

Dave

[jeff_h]

I think the unspoken consensus on the MPG TSB is that overall, it makes very little difference really either way.

 

I believe it's made a small change, for my car was an improvement of maybe 3-5% or so -- however you're right, the much bigger factor is the change in weather, be it really hot or really cold.