Ford C Max, Prius killer?

If the path prediction were turned off, it may return the same higher results as those other cars. There just isn't enough data.

 

Yea. I don't think the result will be 47 MPG though (lower).

 

As they say, YMMV!!!

 

I'm predicting a fuel economy range similiar to the gen2 Prius, which has EPA ratings close to the C-max. I think there will be less outliers though. The weight and aero of the C-max will make the higher numbers more difficult, and the path predicting will help with the lower numbers.

 

Glad to see you quoting EPA and going with fact based results.

 

When would YMMV not be fact-based? People reporting actual fuel usage and mileage are reporting facts, their results, therefore, are fact-based. In my reading of your view on this, though, such fact-based results should be dismissed as anecdotal and given no value.

I'm pressing this point for the purpose of disagreeing with your statement that EPA estimates are "accurate." I'll agree the estimates are improving over time, but this is only as EPA is responding to real-world results. Those fact-based data have real value and meaning to people looking to purchase cars.

While I'm hoping Ford C-Max drivers see increases in fuel economy over time, the early indications are not so positive. Perhaps the car has a steeper curve than most and the engine break-in period will allow significant increases in fuel economy, but it hasn't worked that way for me. I saw increases with both my Gen II and Gen III cars, but these were single digit percent increases, not the 20-25% necessary for those early-reporting C-Max drivers to get up to the EPA number.

What happened for the Gen II was that EPA made adjustments to its model and brought its estimate in line with reality. When I bought my 2007, the window sticker told me the EPA estimate was 60 MPG. EPA now has revised that down to 46 MPG. After my first five tanks of gas and 2,125 miles, my total MPG was 51.0 (measured). After 30K miles, my total lifetime mileage was at 50.8 (measured).

The EPA estimates are valuable and informative. They become truly comparable over time and with adjustments, but I don't think it is correct to say the EPA estimates are accurate or predictive. To me, the EPA estimates will be "accurate" when the YMMV tag can be read to mean "Your mileage will fit within the bell curve centered around the EPA estimate (combined)." Over time, I think that will get closer to reality.

Let's hope it ends up this way for the C-Max, but first indications are that it isn't headed in that direction.

 

EPA estimates are based on a route that doesn't change. In the real world, the routes change. Not every trips will have the same route. For a vehicle that optimizes / adjust hybrid engine operation based on the known route, the estimate is not going to be accurate. That's the bottom line.

 

When Prius zealots claim Ford has "gamed" the EPA results.

 

I wouldn't say Ford is "gaming" the EPA test results. They are doing whatever they can to meet the 54.4 CAFE MPG requirement.

With that said, I wouldn't want to be the PR person for Ford right now. It'll be a very challenging job for the next few years.

 

Two different things.

The EPA mileage is based on rigorous science based testing to provide accurate and comparative vehicle mileage results.

 

It would be helpful if EPA reports a number with a plus or minus value - ie. provide a confidence interval to their fuel efficiency estimate - or do they do that already?

 

The sticker shows the particular vehicle's position within its class of vehicles.

There is a new sticker just unveiled. Here's a link to the site where you can look at the different stickers for gas, plug-in hybrid, diesel, ev, etc.

 

I think a range of expected fuel efficiency would give us a better idea of the variability of results.

 

Yes it would be valuable, and more scientific, to provide standard error estimates. But they do not currently do that.

 

Some people are making assumptions about how the path prediction works. I doubt the cmax drove the route as long as has been stated (1000 miles) to get the fuel efficiency gains.
I will be very curios to start seeing a large number of driver reports. I still remember the rare post here asking why someone was only getting 35mpg or so.
Outliers happen, more reports will give us a better picture.

 

The following is from the owner's manual. It sure sound like the engine break-in includes learning the usual path/route.

Do not measure fuel economy during the first 1000 miles (1600 kilometers) of driving (this is your engine’s break-in period); a more accurate measurement is obtained after 2000 miles–3000 miles (3200 kilometers–4800 kilometers).​

 

Didn't the old stickers give the high and low tested numbers?
Or were those the high and low for the vehicle class, and I didn't completely read the label.

There is the drive train break in, tire break in, maybe suspension break in, or even the calibrating its fuel economy calibration numbers, plus the driver break in. So drawing conclusions of how the lifetime fuel economy car will be from those first tanks isn't wise.

Take the average mpg display in most cars. When reset, after a fill or hit the wrong button, that number can flucuate greatly at first. After a couple 100 miles, it levels out and short term behaviors that caused rapid changes in the beginning don't budge it.

 

Those were for the low and high in that vehicle's class.

I understand and agree there is a break-in for all of these items. I'm sure I had it for both of my Priuses, but my fuel economy was pretty good from the very beginning and hasn't changed much over time.

 

Unfortunately, I trashed all my Prius numbers when I sold the car.
I remember it being in the 40's at the beginning. Which is close to the new EPA numbers, but I was hitting the old EPA before selling.

When I abandon all but the most basic hypermiling techniques(no engine off stuff) with the HRR, I still beat the EPA. Even in the pre hypermiling days for me with the '96 Taurus, I still got the new EPA combined for the car. All over the same route(I took some more surface streets with the Prius, but nearly the same distance).

So even if I had the Prius numbers still, I don't think I could hold them as an average.

 

This is right out of the manual (p.181):

EV+ Mode

Your vehicle recognizes your frequent destinations and allows for more EV driving as you approach them. For example, when nearing your home it should be easier to stay in electric mode. The EV indicator displays EV+ when this mode is active. Frequent destinations are learned by your vehicle. These locations can be cleared through the information display. The EV+ feature can also be turned off. See the Information Displays chapter for more information.

The EV mode usage changes are based on the following criteria:

• 1/2 mile (1 kilometer) from a familiar destination, your vehicle starts to raise the accelerator pedal based EV mode threshold.
• 1/8 mile (200 meters) from a familiar destination, your vehicle is in full EV mode.
• Infrequent destinations have no increase in EV driving.

Note: Learning frequent destination takes approximately two to four weeks of use.
Note: Familiar destination locations are reset through the information display when the trip information is reset.