I have read somewhere on here that it takes 7 seconds to make an auto-stop worth the process economically. So, if you know that you will be moving again before that time is up then is it better to prevent auto-stop? Such as putting it in S?

Before I get flamed ... I know, I could FAS well before (at times), but I have tried FAS on empty roads and though I see the amazing coasting benefits, I realized it is something I cannot feel comfortable in doing in any style automatic, especially in traffic. I would FAS as much as anyone or more if I owned a standard, traffic or not, I have done it plenty of times before Hybrids existed or I knew others used it as a skilled technique. I used it as a stealth mode in my RX-7s which had exhausts and by nature of the beast were a bit LOUD .

So what is the concensus on this subject. I feel comfortable shifting between D and S to control it, or taking the econ button off the climate control. btw, my auto-stops are less than 5 seconds 90% of the time, and I do my best to plan ahead and maximize braking regen.

 

Blue,

Could you please explain FAS to me ???? I'm afraid I don't know the process too well....

 

FAS stands for Forced Auto Stop. It is in simplest form manually shutting your engine off by turning the key backwards. This can be done at stop or while moving. If your normal auto-stop mode didn't kick on when you stopped, or you lifted your foot off the brake too soon (in your case twice), then you can force it off. You will need to be in neutral to start the car back up. Some use this technique while the car is moving to maximize not only the length of the glide in a pulse & glide (P&G) but eliminating the resistance of the drivetrain with the CVT and spinning engine, in non-HCH II cars, it also makes a full fuel-cut, whereas the HCH I shuts down 3 cylinders and runs the fourth lean-burn coasting and decelerating. In a P&G, you would be in nuetral with engine off, then when you reach your personally set minimum speed, your turn the engine back on, wait for the rpms to settle, then shift it back in gear to pulse back up to your set maximum. You could use FAS to coast up to a red light, stop sign, down long hills, etc There is a MAJOR difference in the distance the car can glide with the engine off. You have to make sure you turn the key back to the on position so you have control of your car and your mileage will register. You shut the ICE off by turning the key to accessories for a second or two ... long enough so that the engine doesn't stay running/start back up immediately.

Please don't take my word as gospel, there are those who know far more about FAS with a CVT, I am sure they will chime in and if I made any mistakes or left anything out will happily give corrections or add info. There is nothing wrong with doing it, I think it solely lies on how comfortable you are with it. I drove 4 miles tonight at over 100 mpg without FAS ... but the the next 3 miles to my house was up hill with several stop signs ... so I ended up at 81 mpg average for the 7 mile trip.

Good luck with your mileage, take care, and remember to have fun and enjoy you new toy/car

 

Where did you read that AutoStop took 7 seconds to benefit? I'd like to read that source.

My previous knowledge of the subject says that because the car is started by the Hybrid battery after autostop, that NO FUEL is used for the startup after AutoStop.

 

Getting the car back up to speed is the biggest gas waster of all. If you can prevent starting from a standing stop, you'll save more gas than the auto-stop. I tend to watch the crosswalk signs and if my light is red and I see them blinking (ready to change), I tend to coast a lot more and try to not stop. Then the light will turn green and I don't have to start from a standing stop.

 

When I test drove the HAH, it auto-stopped all the time. Once warm, there seem to be no criteria to limit how frequently it will kick in. I *think* the 06 HCH works the same. The HCH I is the only one that seems to have the "must go 10 mph" rule in order to auto-stop. Having said that, it would seem that if the 7 second rule were true, then the HAH and HCH II would be less efficient - even flawed by design - by employing such a frequent auto-stop strategy. Now if you were using a conventional starter, I can see how the starting process would use as much gas as a 7-second idle. But with the IMA batteries starting, I can't see it. I agree with lars-ss.

 

Just a couple clarifications on those two comments. You can disengage the CVT by using Neutral, so you can 'glide' just as efficiently in Neutral as you can with the engine off. The only drawback is the gas you use to idle the engine in Neutral. Second, be warned that your brakes will eventually loose the power assist once the engine has been off and you've used the brakes a bit. This creates a (personal opinion) rather unsettling feeling that you don't have any brakes. You do, but you need to push real hard. Just know to expect it. Last bit is there has been a ton of discussion, that I won't repeat here, on the issue of engaging the CVT at higher speeds (after the glide, when you restart your engine and go to put it back into Drive). There are those that will say it's no big deal, probably a larger group that will warn not to re-engage faster than 40 mph, and a few that will say it's bad for your CVT. I personally do not FAS at any speed - I use Neutral if I want to glide. I'll only FAS when I'm stopped (stoplights, drive throughs, etc.).

 

How long do you think the Electrical starter will last doing auto-stop at only lights ???? I have a 120K warranty, I just don't want it to go out on me anytime soon.

And one thing: Neutral definitely seems to disengage the CVT, which gives me the general feeling that I can pick up more speed, but it does use SOME gas (to idle). Now, if I just let off the gas, the mpg meter will peg out to 100, and doesn't the ICE cutoff kick in ???? So aren't I in the long run BETTER off keeping it in gear and letting ICE cutoff come on (since it won't use gas) than cruising in neutral ???? Am I wrong about the ICE cutoff ????

 

Blue,

Even IF someone else came and corrected you, I'd still take YOUR word for it. You've got results. 58.6 is pretty **** good, if anyone has tried and put it to practice, its YOU. Good job btw, I was up to 53 for my first two tanks, but then I had broken it in, so I had some freeway blitzes at 80, 90, then 105....

 

I think you're right. If it's a choice between gliding in neutral with the ICE idling on gas, or gliding in D and letting the valves be shut off, the second choice is better. The only way to get better FE than both of those options is to FAS, which is something I will not do.