There's a couple of things to consider here:

1. The system NEVER allows the battery to become FULLY (i.e. 100 percent of rated capacity) charged. This is because running the battery to extremes of charge and discharge will shorten its lifespan considerably. So instead it will charge to maybe 80 percent, and not allow it to discharge any lower than 20 percent.

2. I believe based on the behavior I've observed that the system will, however, allow regen braking to take the battery charge state all the way to whatever charge limit the system has. Once you reach that level a couple of different things seem to happen...first the ICE is spun up (to consume any excess charge?) and the foundation brakes are increased at _nearly_ the same time. The result can be a slight "surging" sensation as the vehicle feels as though it's going to accelerate on you when it starts the ICE, then the brakes apply to compensate.

At any given moment, the hybrid system may be in any one of a number of states. One or both motor generators may be providing power or generating electricity, the ICE may be running or not. Sometimes power from the motor generator will go to the battery and sometimes it will go to the traction motor. In short, this is a very complex system and if they gave you true manual control over it you could never hope to manage it as well as the PCM does...just too many variables to consider.

Just reread my post from before - "ot" was supposed to be "or". Guess I should proofread what I post or start getting some sleep at night.....sorry 'bout that.

One clue is the occasional complaint about how the brakes handle in wet conditions. They seem to slip somewhat when transitioning from regen braking to friction brakes and that has only happened to me at very low speeds (<5MPH) I think the system will use mainly regen braking unless you hit the pedal hard or the battery is mostly full. That's a guess on my part, and maybe I'm overlooking something, but that's what it seems like to me.

My 4WD
Wife's 4WD

Wow - talk about a blast from the past. I forgot all about this thread.

Driving the FEH for the last almost year and a half I realize how so much has changed but how so much has stayed the same. I still prefer L over D in all but wide open highway driving and my mileage is still improving. Gary (in his now world famous LGA thread) has shown how he does better using fake shifts and N.

14 months ago when this thread started we were all just guessing at what we were doing. Now that we know what is going on and how these work, we are trying to master these things.

14 months from now what will we be doing? Will we be looking back at 37 mpg and saying "I can't believe I thought 37 was good" like I am doing looking back at my first 30 mpg tank......? I thought I was "it" when I hit 400 miles to go.....

Amazing......

LOL, No kidding.

What brings this thread up from the dead?

First 4WD Hypermiler

Have you read the FEH FAQ?

Live in Michigan? Let it be known in Michigan Roll Call

Read My Automotive Blog at Rich Rambles

Thanks WScottCross

You've brought up an old thread that identifies Nitranjr (Ray Martin) as the first person that took advantage of low gear in the FEH. It looks like that led Pravas Prime (Rich) to start using "L" also.

Look at the date (6/22/05) before WScottCross brought the thread alive again. It appears, like Ray pointed out, how much things have stayed the same, and how modifications were built on that first discovery.

The people in that thead are the true pioneers of the FEH. I agree with Ray also on his comment about getting 30mpg then and getting 37mpg now. Look at how Hawflake was bringing up patents and how Stevewa was talking about the state of charge the computer would limit charging and discharging for battery life. These people were the cutting edge then, and still remain on the cutting edge now.

Wayne Gerdes has proven records are made to be broken the other day again by getting 180mpg at the Hybridfest Event in a friends (Billy's) Honda Insight. Wayne and these pioneers have helped me push my FWD FEH to over 70mpg.

Who would ever believe that a 50mpg tank would be possible in a stock 2005 Ford SUV? I do! Thanks for all your help guys

GaryG

I found this thread while searching for something and didn't even realize that it was from over a year ago.

My 4WD
Wife's 4WD