Had a Breakthrough Regarding MPG

[stranger267]

Maybe they need oil pressure in transmission above some speed, and this explains why ICU works. But even with this... 63 mph is a very bad chocie having freeway speeds in 65 - 70 mph most of the time, and they can find some compromise to allow better mpg in 65 - 70 mph range. I dont think that it is sharp boundary which can not be changed.

 

(If Energy has different gear ratio it explains the difference as the speed of transmission can be the same in 65 mph hybrid and 85 mph energy).

Edited December 2, 2012 by stranger267

[mikekoz]

     I have been trying this since yesterday. I normally accelerate very slowly, but with this info, I have now been getting to the speed limit quicker (I have not been squealing tires or slamming down hard on the gas pedal!;;p) ). I have also been trying to keep my speed limit at 62 MPH and below. Is this what you have been doing? It seems like this is very similar to the way I usually drive, except to start and get to the speed limit quicker. Also, and this may be in the manual, how do you know the C-max is in EV mode?

[nemonik]

Pulse and Glide

 

The trick to increasing mileage as much as possible is to be in EV mode. I was attempting to stay in EV mode as I was accelerating from stops or slow traffic by babying the gas pedal. What I've discovered is if you accelerate to your desired speed quickly (hopefully the speed limit :)) and then totally let up on the gas EV will kick in. Immediately after EV kicks in resume pushing on the gas peddle being careful not to engage the gas engine again. I then glide as long as I can in EV mode. I repeat this process whenever necessary.

 

 

Okay, maybe I am thick, but what are you doing.  

 

Accelerate quickly, but within legal limits from stop?  Seriously?  And this is the start of efficiency?

 

Then let up?  Like lift your foot  completely of the gas pedal, and wait for the EV mode to be displayed on the LCD?  But them carefully re-apply the pedal, but so as not to re-engage the gas engine.  I take it "EV" means run on battery?  have you equipped your car with barf bags?  I kid, but we'd all at one time or another ridden with someone who drives sorta like how you described, but that isn't what you're saying, right?  Or it actually is that bad, but being you have no occupants, you're not making anyone sick in the car.

[mikekoz]

    I have done this all day today, and on my trips to work and back I averaged about 50 mpg! My trip to work is about 25 miles, half of which is on a beltline with a 65PH speed limit. I stayed in right lane and kepy my speed any between 60-63 the entire time there, and just drove 35-55 mph on the smaller roads. I did not drive any different than what I normally do other than just having quicker starts! Thank you fo the great information! It is informative and so easy to do. One more thing all of you may want to check is your tire pressure. I have found that on every car we have purchased, the tires on it are very underinflated to make the test drives smoother. The tires on my Cmax are rated for 51 psi and Ford had them at 32! The recommended rating on the door is 38 psi, but I have always followed the rated pressure on the tires themselves. You get better gas mileage and wear this way.

[zhackwyatt]

I have found that on every car we have purchased, the tires on it are very underinflated to make the test drives smoother. The tires on my Cmax are rated for 51 psi and Ford had them at 32! The recommended rating on the door is 38 psi, but I have always followed the rated pressure on the tires themselves. You get better gas mileage and wear this way.

Doesn't over inflating the tires cause them to be less grippy? 

 

http://www.popularmechanics.com/cars/how-to/saturday-mechanic-blog/finding-correct-tire-pressure

[stranger267]

Regardig limit - now I am 99% sure that it was because of maximum rpm limit for the EV1 motor (one which sits on the planetary gear transmission, second source on this transmission is ICU and EV2 sits over the output; output speed is EV1 + ICU speed (with some coefficients of course) - when ICU is stopped EV1 motor rotates on the speed proportional to the wheels (vehicle speed) and 65 mph is the speed where this rotation reach the limit - then system must rotate ICU to protect EV1 motor from overspeed. (Something like this; I am not sure about exact terms but idea is simple).

 

So they made a compromise; problem is that they optimized for too low speed - they should do it for +5 more mph and this could save a lot of objections, but in price of lower EPA numbers.

 

PS. High tire pressure improves mileage, but decrease tire traction _in some cases_.

Edited December 4, 2012 by stranger267

[mikekoz]

Doesn't over inflating the tires cause them to be less grippy? 

 

http://www.popularmechanics.com/cars/how-to/saturday-mechanic-blog/finding-correct-tire-pressure

 

   Thanks for the info. I actually did some reading last night and got a lot of mixed information about this subject. One thing that I read that seemed to make sense was to set your tire pressure to 10% below the max stated on the tire. This was so when you are driving and the tire warms up, it does not go over the max PSI. Other vehicles that I have owned had tires that had a max PSI of about 36 and I never had a problem.  However, I think I am just going to put it a few PSI over the recommended rating on the door to play it safe. I did read some online article a few days ago dealing with MPG tweaks and it had mentioned setting the pressure according to the max on the tire. Seems to me now that this is not a good idea and not worth the extra 1 MPG it may give you!

Edited December 4, 2012 by mikekoz

[zhackwyatt]

   Thanks for the info. I actually did some reading last night and got a lot of mixed information about this subject. One thing that I read that seemed to make sense was to set your tire pressure to 10% below the max stated on the tire. This was so when you are driving and the tire warms up, it does not go over the max PSI. Other vehicles that I have owned had tires that had a max PSI of about 36 and I never had a problem.  However, I think I am just going to put it a few PSI over the recommended rating on the door to play it safe. I did read some online article a few days ago dealing with MPG tweaks and it had mentioned setting the pressure according to the max on the tire. Seems to me now that this is not a good idea and not worth the extra 1 MPG it may give you!

My theory with all of this, is that it's not like Ford has a dart board that they throw at and out comes a tire pressure.  I'm sure there is specific reasons they choose that, and since I don't know the specific reasons, I'm going to follow their recommendations :)

[jmckinley]

Maximum pressured on the sidewall is "Maximum Cold Pressure".  It is the pressure to set when the tire has not been driven for a while. It allows for expansion of air in tire with heat which increases pressure.

 

Having said that, however, it is not generally a good idea to run at max pressure.  Big pressure means tire gets rounder across the tread surface, decreasing contact area and therefore decreasing traction.  Also tends to wear the center of the tire.  At high pressure, Tire is also more susceptible to bruise failures such as hitting the edge of a pothole.

 

Recommended pressure on the door frame is not a guess, it's the result of testing to determine the best compromise between handling, fuel economy, tire life and ride quality.  If you have different priorities than Ford, then you can go higher (never lower) to improve handling etc.  but you should stay away from that Maximum Pressure.

[mdkoeck]

If I'm lighted footed and driving for mileage, I get the rated mileage (exception when the batteries need warmed on cold mornings and I'm using heat and heated seats ( live it Boston).  ....btw, I'm not afraid to punch the throttle to pass or merge.  I've taken 1 mile long trips in the high 70s and I consistently get 46 to 51 mpg on my 15 mile commute.  (I find the computer to be 2 to 4 percent off when filling the tank in ford's favor.

 

When I'm running late for a meeting and driving for speed, I get 38mpg.  A 1 mile trip on a cold morning yeilds 16mpg.  Yes 16 mpg.

 

I use pulse driving techniques to move the car into EV mode, I anticipate red lights I have an average braking score of 97%.  Consumer Reports, MotorTrend, etc. are reporting 33mpg.  I can't figure it out unless they have lead feet.  

[C-MaxJaxon]

Keeping the climate control off and just using the heated seats until the engine is warmed up is the key to staying in EV mode. Short trips when the weather is cold and the engine runs continuously will reduce mileage in any hybrid.

[CMAX_owner]

I don't buy it. No way "pulse and glide" could get you 15 mpg more.  I've tried driving this car every way imaginable and get mid-30's.  This car has performed great on flat roads at low speeds. I sat in traffic for a 20 mile commute one day and it got 52 mpg. However, for regular freeway driving (65-70 mph), the mileage is going to be way less, "pulse and glide" or not.  When I drive this car 70 mph on the flat free way with as little gas as possible and no brake, it gets low 30's.

 

You can say what you want about driving 70 mph, but at the end of the day other manufacturers get much better mileage than the CMAX while doing the same thing. I love everything else about this car, but I'm not happy about Ford's 47 mpg claim. If you want to look at each driver individually and figure out what's wrong with their driving style, you can. But in the bigger picture, other car manufacturers are not missing their marks the same way Ford is (with regard to mpg).

 

http://www.latimes.com/business/autos/la-fi-hy-ford-inflated-fuel-economy-20121206,0,1964927.story

[ptjones]

I don't buy it. No way "pulse and glide" could get you 15 mpg more.  I've tried driving this car every way imaginable and get mid-30's.  This car has performed great on flat roads at low speeds. I sat in traffic for a 20 mile commute one day and it got 52 mpg. However, for regular freeway driving (65-70 mph), the mileage is going to be way less, "pulse and glide" or not.  When I drive this car 70 mph on the flat free way with as little gas as possible and no brake, it gets low 30's.

 

You can say what you want about driving 70 mph, but at the end of the day other manufacturers get much better mileage than the CMAX while doing the same thing. I love everything else about this car, but I'm not happy about Ford's 47 mpg claim. If you want to look at each driver individually and figure out what's wrong with their driving style, you can. But in the bigger picture, other car manufacturers are not missing their marks the same way Ford is (with regard to mpg).

 

 

 

 

 

 

 

Well Fuelly is up to 39.9 and climbing.  What's going on, you haven't responded to my post to you. I was trying to figure out what could be wrong. There could be something wrong with your car, I get at least 40mpg at 70mph. That is why I was wondering if you checked your speedometer and odometer with a GPS. This is a good starting point.

Edited December 10, 2012 by ptjones

[AgentCMAX]

 

...I get at least 40mpg at 70mph.

 

Wow!  You must have some very flat hwy to travel on! ;)

 

There are too many rolling hills here in California.  Although I did get around 50-ish mpg readings from the C-Max at cruise-controlled speed of 65mph on a small stretch of the fwy that I thought was pretty flat.

 

It would be nice if we can actually get the EPA test results for the C-Max.  Manufacturers should post their EPA test results so people can see how their cars performed in the EPA tests.  (Ok, I assume they don't post it...if anyone knows where we can access these reports, please post link.Thx.)

Edited December 10, 2012 by AgentCMAX

[darrelld]

Temps dropped into the 20's and my mpg took a 8 mpg hit driving the same route. Just as I expected from a hybrid. My TDI might drop 1 mpg under these temp variations.

 

My Passat TDI is EPA rated at 30 mpg city and I usually get 38, thats an 8 mpg difference in EPA number? Why no big media outcry over the EPAs unfair testing process with diesels? An error in calculation is an error regardless of what direction it takes on the number line.

Edited December 10, 2012 by darrelld

[ptjones]

Wow!  You must have some very flat hwy to travel on! ;)

 

There are too many rolling hills here in California.  Although I did get around 50-ish mpg readings from the C-Max at cruise-controlled speed of 65mph on a small stretch of the fwy that I thought was pretty flat.

 

It would be nice if we can actually get the EPA test results for the C-Max.  Manufacturers should post their EPA test results so people can see how their cars performed in the EPA tests.  (Ok, I assume they don't post it...if anyone knows where we can access these reports, please post link.Thx.)

About 200ft but often so ICE up EV down. Actually I got in my testing of center grill cover 45.1MPG but I think 42mpg is safe at 65 Degress. The disclaimer is your mileage may very.

[AgentCMAX]

Looks like the EPA posts the data for all the cars on their website:

 

http://www.fueleconomy.gov/feg/download.shtml

 

For the C-Max, this is the data...

 

Model Year - 2013
Mfr Name - Ford Motor Company
Division - Ford
Carline - C-MAX Hybrid FWD
City FE (Guide) - Conventional Fuel - 47 mpg
Hwy FE (Guide) - Conventional Fuel - 47 mpg
Comb FE (Guide) - Conventional Fuel - 47 mpg
City Unadj FE - Conventional Fuel - 65.1335 mpg
Hwy Unadj FE - Conventional Fuel - 67.3794 mpg
Comb Unadj FE - Conventional Fuel - 66.1253 mpg
City Unrd Adj FE - Conventional Fuel - 46.7654 mpg
Hwy Unrd Adj FE - Conventional Fuel - 46.8135 mpg
Comb Unrd Adj FE - Conventional Fuel - 46.787 mpg
 

Another interesting info on the C-Max on their website...

 

http://www.fueleconomy.gov/feg/best-worst.shtml

 

The C-Max is categorize as Large for EPA Vehicle Class while the Prius V is considered a Midsize Station Wagon.  They must be going by weight instead of dimension then?

Edited December 11, 2012 by AgentCMAX

[rkk]

 

 

My Passat TDI is EPA rated at 30 mpg city and I usually get 38, thats an 8 mpg difference in EPA number? Why no big media outcry over the EPAs unfair testing process with diesels? An error in calculation is an error regardless of what direction it takes on the number line.

 

Under promise and over deliver - always a good thing

 

Over promise and under deliver - always bad.

[darrelld]

Usually I just roll down to the Thrift Shop in my Prius.

 

 

[RachelnLa]

I chuckle when I see the Mercedes at the dollar store near my house. Saving money any way I can. How you think he affords that Benz???

[mikekoz]

I don't buy it. No way "pulse and glide" could get you 15 mpg more.  I've tried driving this car every way imaginable and get mid-30's.  This car has performed great on flat roads at low speeds. I sat in traffic for a 20 mile commute one day and it got 52 mpg. However, for regular freeway driving (65-70 mph), the mileage is going to be way less, "pulse and glide" or not.  When I drive this car 70 mph on the flat free way with as little gas as possible and no brake, it gets low 30's.

 

You can say what you want about driving 70 mph, but at the end of the day other manufacturers get much better mileage than the CMAX while doing the same thing. I love everything else about this car, but I'm not happy about Ford's 47 mpg claim. If you want to look at each driver individually and figure out what's wrong with their driving style, you can. But in the bigger picture, other car manufacturers are not missing their marks the same way Ford is (with regard to mpg).

 

http://www.latimes.com/business/autos/la-fi-hy-ford-inflated-fuel-economy-20121206,0,1964927.story

 

 

   Consumer Reports is wrong. Ever since I have been doing this so called "pulse and glide", I have been averaging a bit above 47MPG. When we first purchased the Cmax, the AVG MPG on it was about 38.x. It is now 42.8 and I have been driving it like this for a few weeks now. My average goes up a little bit daily. Like you, however, we did get about 36-38 MPG on a recent trip where the speed limit was 70mph, but I knew the car was not going to work in EV mode above 63 MPH anyway. That is still higher than most cars on the road and all cars get lower gas mileage at high speeds. I still think it is odd how gas mileage in cars, up until hybrids became popular, has gone down over the years. I drive a Honda Civic back in 1984 that got 46 mpg around town and 55 on the highway. The next year, they made a car that beat that! Ford now seems to be ahead of the pack as far as gas mileage goes.

[valkraider]

Cars have been getting larger and heavier and more powerful. That's why the older cars seemed to get better economy.

 

Now they have all kinds of extra goodies and equipment, lots of safety and emissions gear, and 200 horsepower motors we don't need. And they are big. I think an old Honda civic could sit in the trunk of a new Honda civic.

[mikekoz]

Cars have been getting larger and heavier and more powerful. That's why the older cars seemed to get better economy.

 

Now they have all kinds of extra goodies and equipment, lots of safety and emissions gear, and 200 horsepower motors we don't need. And they are big. I think an old Honda civic could sit in the trunk of a new Honda civic.

 

 

LOL...you are correct! My old Civic was not very big and had NO get up and go whatsoever!

[JayCo59]

I know the Energi is capable of speeds up to 85 mph in EV, not certain why Ford chose 62 mph except to ace the EPA test.

I would think it has to do with the size of the battery, the Energi has a larger battery, just look in the back to see the (lack of) cargo room in the Energi version.

The larger battery can supply more current for a longer time.  The larger current demands at the higher speeds are what is probably limiting the speed to 62 MPH.

Could they have but in a few more batteries to get the speed to 65 MPH, sure, but everything costs $ and may be they where out of room without taking up additional cargo space?  You're point about "Acing" the EPA test could be a valid point. If 62 MPH gets a good number from the EPA test then that may be what the engineers did.