Porscheguy

Regarding the A/C, I guess I assumed the compressor was electrically driven and would have little impact on fuel mileage. That would seem to be the case since the A/C functions with the ICE off in my RX.

lamar411

congrats! thats some serious dedication.

hyperme

The battery discharge thing scares me. I remember when I first started hypermiling, I'd always run the battery down to 2-4 bars at the end of my cummute. I was unaware at that time that it took the ICE that much longer the next morning to recharge it. KG, I believe it was you that said you keep the battery pack as full as possible when you drive. I tried that and it seemed to improve my mileage. Now my battery pack is usually (60-70% of the time) completely full or down only 1 bar, but that's as low as I let it get.

hyperme

The issue is if you let the a/c deplete the battery, your ICE has to work harder (read-use more fuel) to recharge the battery.

KGenaidy

You are absolutely right about the discharge being quicker and the increased potential for the "recharge" hit. It certainly is brutal in terms of lowering mpg .... but this may be a thing that's only an annoyance for hypermile inclined drivers. It's happened once this summer to me in a construction area.

All that being said ... summer in TX and having AC on ... trumps all else. Just another example of trade-offs and choices

noku

Awesome mpg!! I really struggle just to get 34mpg although I run the a/c 100% of the time and live up a long hill.

What happens to the scangauge when the ice turns off? Do you know if this also applies to the ultragauge?

Good luck on your next goal.

hyperme

Here's what happens to the ScanGauge when the ICE cuts off:
1. RPMs drop to zero
2. GPH drops to .03 (because of a quirk in the SGII, it doesn't go all the way to zero, but no fuel is actually being used)
3. Trip MPGs start to climb

Not sure about the Ultragauge, but logic would dictate that it should do the same.

I WAS doing really well on this current tank. Through 550 miles I was at 72.5 mpg actaul (76.2 on the dash MFD). Then something completely unexplainable happened to my car last week and my MPG dropped from approx 73mpg per day down to just under 60, that's about a 20% decrease, ouch! I have no idea what happened, but it's pretty frustrating. Weather's been about the same, wind hasn't changed much, driving style is unchanged. My tank average has been dropping every day. In 3 days of this, it's dropped to 70.8mpg actual. I'm taking it to the dealer Tuesday.

KGenaidy

I had a similar thing happen earlier this year.

Turned out that the HS was in "normal" mode and not "eco". It had just been to the dealership for work. Since I always have it in eco mode ... i didn't think about it for 3 days until I noticed the dash indicator wasn't on.

TheAirman

I've read some of your informative posts before on hypermiling and can't wait to try it a little more in my own vehicle. I was using some of the techniques I read about in my M3 and was getting a whopping 25 mpg's !!
But now, if you don't mind, I have a question or two.

First, how would you have control over the level of charge or discharge in the battery pack? Doesn't the car itself control this, or is it just another method of altering your driving style?

And second, could you give us a run down of maybe one day of the techniques you use in your normal work day commute to get that kind of mileage? I know on mine, living here in Western PA, which has more hills than San Fransisco, sometimes that can be used against you, and sometimes that can be used to your advantage.

noku

Thanks for the info. I wasn't sure if these types of devices would just turn off with the ice off. I hope the dealer can help you out with the recent lower mpg's. Besides tire pressure, additional weight, clogging air filter or catalytic converter and maybe quality of gas and no check engine light I would be at a lost as well.

hyperme

Hey Airman,
Your driving style definitely impacts your battery level. Read on:
1. Not sure if you are aware but the 1st 50 seconds (approximately) of your warm-up cycle uses basically only battery (the engine is used to warm up the cat converter). So if you accelerate heavily during that 1st 50 seconds you will be discharging the battery more than you think. I always use a Warm-up P&G and that drains the battery more slowly.
2. I never use EV mode (activated by pressing the EV dash button) since that uses only battery for propulsion.
3. If you accelerate slowly from a stop, and you see only the yellow arrows from the battery to the drive wheels, you are, of course, using only battery for propulsion. I try not to do this too often.
4. The more you use your headlights and DRLs, the more battery you use. I keep my DRLs off.
5. While accelerating, if you see only orange arrows, as opposed to both orange and yellow, you will be charging your battery faster. To get only orange arrows, you will have to accelerate more slowly.
6. Any accessories you use will discharge the battery, hence I don't use a/c or heat (the 2 biggest drains on the battery). For long glides, I turn off my radio and close my Nav screen.

These aren't the only items that affect battery charge, but will give you an idea how you can impact your battery level

hyperme

I use most of the hypermiling techniques every day. I P&G nearly 100% of the time I am driving (I don't if I'm ascending a steep hill, I use DWL in that case). Some of the the techniques I use are: P&G (pulse & glide); DWB (driving without brakes); DWL (driving with load); PP (potential parking); RR (ridge riding); Warmup P&G; Face out parking. The 2 most effective techniques are P&G and DWB. If you use just those two you will see a dramatic increase in your MPGs.

BgLftyinaz

I don't fully understand how pluse and glide actually work.

I've read a blog from mike with a prius and a hobbit. Unsure if I really know what to do.

I get up to speed and then try to glide,then accelerate back to speed and glide again.I fee like , i slow down to quick before needing to speed up again..

Do you have a blog to read?

Luv2xl

iTrader: (5)

wow.. i am at a loss for words.. Good stuff!

Rdrcr

Wow!!! That's freaking awesome!

Mike