Article: EPA to Fortify Certification Oversight in Wake of Mileage Controversies

[gone-ot]

"Gaming" the EPA fuel economy tests will become all the more 'invisible' as we get closer to the EPA-CAFE-mandadted 55 MPG numbers.

[aerohead]

Originally Posted by tjts1

Several billion real world miles logged by owners would beg to differ.
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I think that the premise for the EPA testing comes down to repeatability.And a laboratory environment is probably the only environment in which one has a chance to cover every conceivable variable,really locking down the numbers.
If the car maker's testing follows the protocols,their results would be the same as if EPA Mobile Sources did the testing themselves.
And EPA has never suggested that what they put on a window sticker is what you'll realize in real world driving.It's just a guide.

[Xist]

I cannot imagine them doing this, but I wonder if they could make cars perform better on the EPA tests and worse when hypermiled.

Can you imagine the nerd rage that would ensue?

Oh, it looks like it has already started...

[gone-ot]

Take your pick:

EPA lies

EPA damned lies

Manufacturer lies (errors).

All the above.

[brucey]

You forgot statistics.

[niky]

Originally Posted by brucey

If I'm honest, I'm having a real hard time matching the EPA numbers in the new car, versus the old car where 50% over EPA was an obtainable number. I don't know if my hypermiling skills has eased up or if the EPA Cycle #s are a little optimistic to begin with.

Still satisfied with the mileage, but just not blown away I guess. I've also read that the mileage improves as the engine/car breaks in as well. Just seems odd still.

It's all about cycle-beating.

As greater and greater electronic control allow ever more specific engine tuning, manufacturers are gaming the test by making cars with very specific gear ratios, shift points and engine tuning, all designed to perform very well within the narrow performance window the EPA is test in.

Which means, drop your revs/speed or raise your revs/speed either way and you're out of that programmed "EPA Window" and into "regular driver" territory... where the engine is tuned more for power and reliability than ultra-lean cruising.

It's why more and more naturally aspirated cars are coming with a stupidly U-shaped torque curve. Gaming the EPA. The bottom of the U fits neatly into their planned acceleration profile.

Be nice if the EPA mandates economy over a wider range of situations. If you have to game the tests at ten different set speeds (say, from 30 mph out to 70 mph) and over three different acceleration rates... then the car is programmed to perform well for 90% of the people out there. That would be enough.

[dirtydave]

They should redesign the entire thing and just do a point system. You got a low .cd ? Have some points. A nice cvt in this year's model vs the old 4 speed auto? Points. Cut weight, redesigned mirrors. Ect.

This needs to stop my grandfather has a brand new Malibu a 4 cylinder and gets 18mpg. Epa says 23-29 he doesn't speed or drive crazy just normal lightfoot driving. Not a hypermiler but he should get decent mileage. He will upshift the automatic into 6th at 45mph. Still 18 mpg. Tires are good. Everything is good. The epa allowing cheating is not.

[Frank Lee]

There has to be something wrong with that car.

[jakobnev]

I think dumbing it down to two numbers makes the whole system broken by design.

[MetroMPG]

There has to be something wrong with that car.

Oh, I don't know.

My mom, who literally drives like a grandma (because she is one), would get ~20 mpg US from the last 4 cyl Camrolla she had. Usage? Almost all short trips. The car probably never reached full operating temp the whole time she had it. I shudder to think what she got after Dad replaced it with the V6 model.