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I tried a FAS for the first time today as I was coming to the end of a short trip and it came off without a hitch. I just put it in neutral as I crested the hill, backed the key off one click to kill the ICE, then turned it forward to re-boot the ECU. I made it about 2/10ths of a mile before I had to re-start for a left turn, so I just put the tranny in fifth and let the clutch out at ~28mph. To my surprise the engine re-start was virtually seamless. However I have two questions.

First, is this "bump starting" approach the best way to do it while on a roll? My gut says yes because it will save the starter, but my mind wonders if I am going to kill my clutch instead.

Second, how long can one go before running out of sufficient vacuum to operate the power brakes? I've always had nightmares (no kidding) about driving a car downhill and not being able to bring it to a complete halt and I'm wondering if this is what I'm being warned of. Would it make sense to install a vacuum pump and reservoir like many turbo vehicles have or is that just unnecessary?

I tried a FAS for the first time today as I was coming to the end of a short trip and it came off without a hitch. I just put it in neutral as I crested the hill, backed the key off one click to kill the ICE, then turned it forward to re-boot the ECU. I made it about 2/10ths of a mile before I had to re-start for a left turn, so I just put the tranny in fifth and let the clutch out at ~28mph. To my surprise the engine re-start was virtually seamless. However I have two questions.

>>> Thats the way it works. :)

First, is this "bump starting" approach the best way to do it while on a roll? My gut says yes because it will save the starter, but my mind wonders if I am going to kill my clutch instead.

>>> Ive never killed a clutch from bumping. Ive smoked them from drag raceing. Holding on a hill and such. I use the key and clutch. Favor the clutch in my Civic cause there is no Navi reboot when useing the clutch.

Second, how long can one go before running out of sufficient vacuum to operate the power brakes? I've always had nightmares (no kidding) about driving a car downhill and not being able to bring it to a complete halt and I'm wondering if this is what I'm being warned of. Would it make sense to install a vacuum pump and reservoir like many turbo vehicles have or is that just unnecessary?

>>> I always take a car out to a lonely strech of road or into a very rual area and find out just what the vacume sysem will do. How the brakes will work. And also how the car breaks without vacume. I see how they steer and see if Im comfy with it. As it turns out our Accord and Civic will hold vacume for a 2 mile FAS or so. The brakes can be used several times without a problem. Also in the rare event that I would loose vacume I also have enough foot to stop the car and the hand brake is right there. Im able to steer the cars with the ICE off. I FAS alot down the street to my house and whoop it right into my driveway. All with ICE off. Turn corners in the city, HWY's, or interstates.

Testing the car and your limits in a safe area is a must! The skills will come. As for a vacume pump and such. I dont need one and I do hwy speed FAS 1.5 miles almost daily. And still have brakes when I refire the ICE.

psy

Hi Brick:

___I will clutch start in a taller gear then I would normally be in for accelerating just so that on the hook up, she stays around 1,000 – 1,100 RPM’s. If I am traveling > 35 mph, then I drop her in fifth and I receive what I receive. I will alternate in maybe 2 Clutch starts to 1 gear reduction starter around town. Out on the highway, it usually a clutch start and up I come. All I can say is that 12V batteries, clutches, and starter motors are tough. The 05 Accord has maybe 7,500 - 10,000 gear reduction starter motor starts on her 45K + miles and she is as strong as ever. I have noticed a weakening battery given the 80% or great DoD cycles she has seen in the dark and extremely cold winter temps over the past 2 or 3 months. The Ranger pulls > 5K # trailers in the summer including backing it up an ~ 10’ incline over 200’ into the garage and her clutch is as strong as ever at almost 30K miles … YMMV however.

___I cannot tell you where your 02 Accord will lose brake vacuum as you have to find that out for yourself. It is never instantly in anything I have ever driven but I usually have 3 - 5 good taps or holds before the ever present brake assist disappears in both the Accord and the Ranger. Because you are decelerating under a FAS, you should never really have to touch them as traffic should be moving faster/pulling ahead before you go ICE-On again. If you find traffic slowing faster then you are and need for multiple taps, you have 3 choices. Go ICE-On to bring vacuum back and FAS again, hang on the binders while you do have assist to really bring yourself down below the speed of traffic around you or three, ride your E-Brake after you have lost assist. I have never used the third option at higher speeds because you could spin out quickly with just the rears locking up let alone your much longer braking distances but my hand rests on the lever after a minute or two inside of a long FAS just in case ;)

___Some time in the very near future, get out on a desolate country road, bring her up to maybe 70 mph, and start tapping away while in a FAS. You should find that after 5 or so uses, the assist is gone due to lack of vacuum but I would be guessing in terms of your 02’s capabilities. As cars get older, the vacuum lines do indeed lose their holding capability from small leaks in joints and such. Just know the limits and test them every once in a while.

___Finally, be darn careful as you are powerless and can be brakeless in a FAS. The only time you should find yourself accelerating into slower traffic w/ ICE-Off is when approaching a D-FAS opportunity and as far as that is concerned; you have full assist as you have not touched the brakes as you slowly crawl up on your target. If you come in a bit to hot, pull into the left lane and let the aero-drag do its thing until the target has again pulled ahead and you can duck in behind to grab what ever is available as said target continues to pull away.

___I hope this helped but again, be very very careful as a non-hybrid was not really designed for ICE-Off like hybrids are …

As an edit, I overwrote Psy's post as I was typing this one up. Sorry Psy.

___Good Luck

___Wayne

Thanks very much for both responses :) Thorough and informative as usual. I'll take some time to test out the brakes and steering in an isolated spot before I put FAS into daily use.

Hi Brick:

___About the steering … Let me add that I love non-assisted steering at any speed above 5 - 10 mph. The difference between ICE-On and ICE-Off at speed is still significant but I detest its lack of feel with what might be considered the best speed compensated assist available in our Honda’s. In the Insight, I actually pulled the EPS (Electric Power Steering) fuse to disable it entirely! Anyway, until you are below ~ 10 mph, I think you will really like the additional feel you have without that overly compensated assist in most any circumstance including going lock to lock if you were to ever come into a corner to hot and had to pull it out of a power off slide.

___Good Luck

___Wayne

I suppose a particularly avid and mechanically-adept hypermiler could find a way to rig a speed-sensitive electric power steering that only functions at 10 or 15mph and below. As you get your steering feel back you save a little parasitic drag on the ICE. At what cost I have no idea.

plus with no power steering you can't burn your rubber as much when your moving at super slow speeds, many underestimate the power of power steering and steers way too much before attempting to move their car an inch.

but in some circumstances your forced to bite the bullet like parallel parking.

forgot to add, i FAS into parking stalls. I can have ICE OFF too in the parking alot!! Prius can't get all the glory.