After reading the owners manual and a multitude of posts telling me to expect better MPG after the first 4000 miles, I have ask this question: (yes, I realize this has been touched on in several other threads.)

What percentage of the break-in period is car and what percentage is driver?

Does the FEH/MMH actually run at less than optimal effeciency during the break-in period in order to condition the battery and "take it easy" on the new engine?

Or is this just a myth supported by the fact that drivers get better at taking advantage of a hybrid in the first 4000 miles? Any Ford service techs care to chime in with the facts?

Yes. There is both battery conditioning and and computer "learning". The fact is you would be hard pressed to get a new FEH/MMH over 30 miles per hour in EV mode before you put a few thousand miles on it (aside from rolling it down a hill!). You also would have a hard time for keeping it in EV mode for more than a half mile or so. Obviously, this coincides with the driver learning the vehicle too. That said, the vehicle break-in period limits what the driver can do.

-Tim

2006 Mercury Mariner Hybrid AWD
Black with Pebble interior
Premium Package with Nav & Moonroof



Current ODO: 26,152
Typical Drive: 20 min crosstown in heavy traffic (3.5mi there and back twice a day)


532 Gallons of gas saved
That's 10,642 lbs less CO2 emitted

Er.... you mean 30MPG not 30MPH I hope. I'm pretty darn shure she'll do freeway speed right off the factory floor if the workers duck out of the way.

From what I experienced in my break-in period, I'd say it's about 75% mechanical "conditioning & learning" and 25% driver C&L.

The vehicle does need some conditioning and learning to "dial in" to the best efficiency, but it does also take a bit of "reprogramming" of the driver to get the most out of the vehicle's technology.

I found most of the reprogramming of my habits was trying to figure out the tricks for how best to keep it in EV as long as possible and trying to figure out the pulse & glide tactic - that takes a lot of practice. It takes quite a while to figure out just how much pedal pressure you can apply but still keep it in EV. I actually found this to be fairly difficult in the first 3,000 miles because you're also kind of fighting the mechanical break-in of the vehicle while you're trying to figure this out. It won't let you get into EV very easily during the break-in period, and it gets to be frustrating at times. But once the vehicle has broken in it's fairly easy to get it into EV - by the "reprogramming" of both the driver and the vehicle.

Actually, I meant to write 30mph but left out "in EV mode". I have edited my post to correct that faux pas. But, since you mentioned it, you are probably right that getting 30mpg is tough too early on.

Thanks.

-Tim

2006 Mercury Mariner Hybrid AWD
Black with Pebble interior
Premium Package with Nav & Moonroof



Current ODO: 26,152
Typical Drive: 20 min crosstown in heavy traffic (3.5mi there and back twice a day)


532 Gallons of gas saved
That's 10,642 lbs less CO2 emitted

We did not see a significant improvement in the mpg on our 08FEH until just after 9,000 miles.

At just over 9k, we had our first oil change done. We used 5-20 fully synthetic oil.

Not long after that, our fuel mileage increased without changing our driving pattern or habits..

We consistantly get 38-40mpg in our 2wd Feh. Other than special trips, ALL of our driving is done on roads 40mph or less.

On a recent trip to Miami (200 miles each way) we averaged 36.6mpg all highway 65-70mph.

The weather has been cooler due to winter, we have been using the AC less, we haven't stopped using it however.

When we first got the FEH, we took a trip to Daytona and were only able to get the advertised 30mpg highway.

Improvement in your mileage will definately come.

I am not sure of the reason(s) for this improvement exactly.. but I am VERY happy with the end result. Since the increase we have never gotten less than 500 miles from a single tank and got just over 600 one time when I somehow got almost 17 gallons to fit in there. I still have not been able to get that much in, or get that many miles since.

hope this info helps..

08FEH

@Tim -- Thanks, that's the verification I was hoping for, and it is, in fact, quite encouraging. First, because it means I can expect my MPG is to keep improving (I just topped 1000 miles). And second, because I have to give some respect to Ford for building a break-in period into the system. New cars have always needed this, but a computer controller enforcing it (both for the ICE and battery) is far more effective than a couple of unread pages in an owners manual. Not to mention, I'm sure the engineers have been pressured by marketing to improve the off-the-lot MPG -- you hate to have dissatisfied customers in the first month of ownership. I'm glad the Ford engineers stood their ground.

At 9000 miles, we're not seeing any improvement. Since we got the car in July, mileage increases have been more than matched by temperature decreases and gas mileage has gone down, not up. We're hoping for an early spring and quick turnaround in this trend.