Evan,
None of the hybrid benefits are available until the car is "warm." I assume that the engine must run long enough to raise some fluid temperature to some specific level. Perhaps those with Scan Gauges can give some precise numbers on this question? What "warm" numbers must exist before the hybrid features become available?

On some 25 degree days in Iowa, it took about 10 minutes of 30-40 miles per hour driving for warmup; last weekend with the outside temp near 70, it took 2 minutes or less.

Here's what I observe on start (which is still very strange to me with no sound of a starter turning the engine over; just turn the key; engine is on). The hybrid light row has no activity out of the three possibilities:
green bars to left= hybrid batt recharging;
green ECO light at center= Variable Cylinder Management (VCM) is deactivating 3 cylinders; blue bars to right= Integrated Motor Assist (IMA) is providing battery power.

I don’t have Navi, so the averaged trip computer (updated every 10 seconds, according to Honda) is my reference point. On my daily commutes on 30-40 degree mornings, if it’s early in a tank of gas, no matter how carefully I drive, I lose around 2 mpg in the 5+ minutes of warmup, which does include some hill climbing. Usually, I’m driving around 45-55 when the first signs of hybrid activity occur–green bars to the left, indicating hybrid batt charging. I don’t recall ever seeing any of the other hybrid indicators appearing first. There seems to be some delay before the other two features are available, about a minute I’m thinking.

After the magic warmup threshold, if I throttle back a bit, the green ECO light comes on. If I’m going at speeds less than 50, I often see a sudden IMA surge right after the ECO light comes on. This is what I mean by the IMA “volunteering.” Though it’s not harsh, I do feel a noticeable power surge from the IMA and notice some miles per hour gain. The IMA assist stops as suddenly as it started. After that, again in speed ranges of 50 and below, the IMA “volunteers” on slight grade elevations, with more or less bars of assist depending on steepness of grade; sometimes the ECO light goes off during this kind of IMA activity. I see very little IMA “volunteering” past 55 miles per hour, even on grades steep enough to cause ECO to go off. I can choose to “call” IMA here if I want.

I hope I’m getting around to answering your question. Until the car is warm, nothing you do can call the hybrid features into action, and warmup time is relative to air temp and rpm of the engine (btw, does anyone think this car has a really fast idle on cold start? I’m using the brake backing out of the driveway.).

For me, green bars to the left appear first, followed within a minute by the other two signs of hybrid features. As soon as IMA has once appeared, I can “call” it by throttle pressure. Slow gradual pressure won’t call it usually, even with a hill. But, if I press the throttle more firmly (still nothing near the floor or WOT), I can call the blue IMA bars up, and I’m getting better at “selecting” how much throttle will call how many bars of IMA. I do think that the best mpg is attained by driving to keep ECO on as much as possible, and a soft pedal foot and practicing what Wayne and other experienced hybrid drivers on this board call “driving to load” are effective ways to “call” and control ECO.

On hills with gradual grade, I’m getting more and more impressed with how little backing off the throttle and slowing I have to do to keep the green ECO light (and use of only 3 cylinders) engaged. But, if the hill is longer or steeper and I have to give up too much speed to keep ECO, I “call” IMA by increased throttle, and by controlling throttle pressure, I’ve been able to keep IMA boost up a fun, twisty, 3/4 mile hill, actually increasing speed, and losing only about one to two-tenths mpg. After this hill climb, my batt bar level is usually down to 2 bars, indicating that in serious, tall climbs, the battery charge to power IMA wouldn’t last past a couple of minutes at most (I’m guessing here).

Of course, after warmup, you can call IMA for passing; you don’t have to go to WOT to get all the blue IMA bars lit up. I notice about a tenth mpg loss after a spirited pass (50-80 miles per hour surge fairly quickly, not a gradual pass since I’m mostly on two lane roads). Easing the throttle after such a pass will produce both green bar batt charging and the ECO light.

I notice a lot of IMA “volunteering” in stop and go, 10-30 miles per hour conditions, and I’m not aware of anything I’m doing to “call” IMA there. Though mpg goes down in stop and go conditions, the combination of IMA and motor shutoff at sub 5 miles per hour and stop helps minimize the loss. MPG goes up immediately and quickly at 35-45 if you can avoid stops and keep ECO on.

Let us know what you are experiencing with your HAH; I don’t want to be the only one blathering on about what surely will be a passing obsession with the ECO game :=).

Lewis