Newby needs advice

[goodella@hartwick.edu]

I want to post what I've been doing, and please tell me if you think my engine or tranny or anything else will blow up from these hypermiling aspects I've been trying with my Subaru Legacy:

If there's a big hill, I shift N, key off ICE, wait a second, then turn the key one notch so electronics come back on. I loose power steering which isn't a problem at speed, and power brakes which gets annoying when after a few pumps of power are used up. Where I drive there is sometimes big hills (I've been over 8 miles on a single coast, several over 3 miles is normal). When the speed goes too low I key on the ICE, rev a tiny bit (1-2k) and shift back into D. Without the rev it jumps a bit. So far this seems to help FE very well. I just jumped from 23mpg to 33mpg since I can coast for over 15% of my drive with the engine completely off. Is much gas saved by keying off the ICE? Would I be better to just stay in N?

An accident that occurs occassionally from this is that I key off but forgot to shift to nuetral and it jumps back on. That seems not good, but I think I've read that some people here were doing that to start their cars instead of using the key.

One annoying bit is that I hate turning the engine off at night because on my car the lights completely go out until I turn the key back for them. So if a car is coming and I want to power down, I have to flash them. [Edit: By that, I mean the lights are only out for a second] I don't think there's a way around that other than making some switch on the dash route power to the lights regardless of the engine on/off. I think that's fairly unique to Suby's. Anyone try that?

Any tips of hints or "holy-crap don't do that!"s will be accepted! Thanks.:D

http://www.gassavers.org/gaslog/sig.php?id=587 (http://www.gassavers.org/garage/view/587)

[ELF]

Welcome to GS, I really envy your coasting, around here I can get maybe 1 mile tops. But that is rare. You seem to be doing well so far, don't think coasting will harm anything.
Thats is weird with your lights, I have never owned a vehicle that turned out the lights when you key off.

[skewbe]

wow, 8 mile glide, that would simplify things. Sort out them lights!! My DRLs used to turn off on my metro when the engine stopped, but not the main lights.

FYI, you might want to consider a modification to make it rv towable (to keep the tranny bearings lubed). 8 miles is a long way on atf and no circulation. You will definately see better mpg results with the engine off, but you have to consider the design limitations of your transmission.

[goodella@hartwick.edu]

ELF, I've never driven another car that had the lights go out. It's great since I can never run the battery by leaving lights on when the car is off, but it also means I can't shut off the engine without blinking them off.

Skewbe, maybe if I restart every few miles when there's a huge glide it would lube it up again enough to safely coast more.

I read through my manual, and it recommends for towing on all wheels not to exceed 20mph and 31 miles. Can I extrapolate that to 50mph for 12.5 miles?

http://www.gassavers.org/gaslog/sig.php?id=587 (http://www.gassavers.org/garage/view/587)

[Hockey4mnhs]

i think you will be fine. you wont be doing 31 mile costs so your tranny will be ok
also i just checked your garage and i saw that you took off AWD how did you do that?

[goodella@hartwick.edu]

Hockey4mnhs, Something about my AWD was close to broken so the mechanic told me to shut it off or pay $1100 to fix. Under the hood there's a cover labeled AWD that I put a spare fuse connector in, and on my dash it now says FWD. When I get stuck in snow or driving offroad I can take the connector out and it goes back to AWD (and hopefully doesn't brake!)
http://www.gassavers.org/gaslog/sig.php?id=587 (http://www.gassavers.org/garage/view/587)

[Raccoonjoe]

Subarus.....ahh, the glory!!

While I love the cars, and you have some very good ideas.....I would try a tank or two leaving your engine idle in N while you're coasting down those hills. Think of it like leaving the clutch pushed in on a standard transmission. Working an auto tranny without lubrication (coasting engine off) is a recipe for disaster!

Think of it this way: Your manual says that you can tow at 20 MPH for 30 miles. That's kind of like saying you could put your hand on the stove for 3 sec. before burning it. Would you still do it?? Transmissions are expensive...I just don't see saving $.75 per fill worth the risk of grenading a transmission.

I guess this would be the "Holy crap!! What are you doing!?!?!" post.....but keep up the good work!!

[Ryland]

I'm glad that someone is finely reading their manual! it's there to be read, and you alwas learn something.
if it says not to tow the vehicle over 20mph, then I would say the same goes for coasting, but it is up to you to deside what works, and there is a differnce between towing, and coasting, mostly that in towing you are not in the vehicle to hear and see what is going on.
most of us who engine off coast have manual transmitions, not automatics, so alot of the expearince in this area will not apply.

I've gotten in the habbit of killing my engine on a few hills, one with a speed limit of 25mph, and to stay under that speed I use my hand brake, setting it lightly about 4 clicks up gives me just enough resistance that my car will not run away, and leaves me enough vaccum to use the normal brake pedal 3-4 times.

[cfg83]

goodella -

Hockey4mnhs, Something about my AWD was close to broken so the mechanic told me to shut it off or pay $1100 to fix. Under the hood there's a cover labeled AWD that I put a spare fuse connector in, and on my dash it now says FWD. When I get stuck in snow or driving offroad I can take the connector out and it goes back to AWD (and hopefully doesn't brake!)

Wow, the AWD drive is one of the reasons I have not seriously considered Subaru's in the past. I have always been LA urban, so I can't justify AWD. Even though you would still be carrying the extra drivetrain weight, I wonder if this is a "Subaru Mod" for FE.

Would this mod work with Manual transmission Subarus?

I second what Raccoonjoe says. Other people's auto transmissions have worked fine with (i.e. repete86), but it's hard to know if your transmission is "compatible" with this strategy without alot more research.

CarloSW2

[cfg83]

Ryland -

I'm glad that someone is finely reading their manual! it's there to be read, and you alwas learn something.
if it says not to tow the vehicle over 20mph, then I would say the same goes for coasting, but it is up to you to deside what works, and there is a differnce between towing, and coasting, mostly that in towing you are not in the vehicle to hear and see what is going on.
most of us who engine off coast have manual transmitions, not automatics, so alot of the expearince in this area will not apply.

I've gotten in the habbit of killing my engine on a few hills, one with a speed limit of 25mph, and to stay under that speed I use my hand brake, setting it lightly about 4 clicks up gives me just enough resistance that my car will not run away, and leaves me enough vaccum to use the normal brake pedal 3-4 times.

What is the wear and tear factor on the (rear drum?) brakes in that circumstance?

CarloSW2

[brucepick]

... What is the wear and tear factor on the (rear drum?) brakes in that circumstance? CarloSW2

I wore down the e-brake on one of our cars by using it when the regular brakes were grinding.

The cars my family has been driving all have 4-wheel disk brakes with separate drum brakes in the rear for e-brakes. If yours is set up this way then I think the e-brakes probably not designed/built for regular frequent use. Aside from setting the brake when parking of course - there's no friction rubbing of the brake shoe/pad when parked.

[brucepick]

...
Would this mod work with Manual transmission Subarus? ...

I looked into Subarus as an alternative to the Volvos we've been driving since '95.

The auto-trans awd Subies can be forced into fwd mode by inserting that fuse. I'm pretty sure the standard tranny ones don't have it - but of course they give you better FE than the autos anyway.

FWD places its own "tax" on FE just by all the extra rotating mechanicals but if you need it for your climate or for a long steep snowy driveway, then a Subaru is better for FE than most other options.

[brucepick]

Somewhere I saw a list of gallons-per-hour fuel consumption for idling. Something like between .2 - .7 gal/hour, depending on engine. (A ScanGauge will show it.) So coasting in neutral while idling will get you something like 100-200 mpg. But of course the FE is even better if you don't run the engine at all.

I'd follow the manual's advice and not coast with engine off over 20 mph. Trannies are way too expensive.

By way of comparison the rear-drive Volvo trannies are flat towable only up to 40 mph for 40 miles. In regular use they're pretty much unkillable; they usually go 250-400 K miles before neglect and owner poverty kill the car off, and the tranny is still working (engine also!). So if a more typical auto tranny says to limit flat towing to 20 mph/20 miles, I'd believe the book.

[brucepick]

About the headlight thing...
Our Swede cars appear to have the same system.
No headlights unless ignition is on.

Headlight switch receives incoming power only when ignition is on.
Headlight switch output goes to a relay.
So there's no output from switch to relay unless ignition is on.

If you instead supply the headlight switch with power from another source you can have headlights any time. Assuming it's set up the same as on our cars...

A basic relay has four terminals. Two for input side, two for output side.

At the "input" side, one terminal is hot from the headlight switch, the other goes to ground. In between these is a coil which operates a magnetic switch which controls power through the relay's output side.

The switch defaults to the "off" position so when there's no power coming in from the headlight switch, the headlights are off.

Output side: One terminal is hot from the battery or fuse panel. The other feeds out to the headlights. When the magnetic switch closes, the hot power is fed out to the headlights.

Hope this helps.

[goodella@hartwick.edu]

I might stop using the EOC at higher speeds than. The car is pretty old with 180+k miles and worth under a thousand now, so I wouldn't cry if it died, but at the same time I don't want to be the killer. I don't see a reason to stop EOC in town when coming to a stop with slower speeds (such as coming to a stale green or red).

As for modifying the headlights to stay on, I think I'll just pass. Too much work for something I can live without. I rarely drive at night, so it's not a big issue.

[Raccoonjoe]

I have noticed that when trying to EOC into parking lots/stop lights with my Jeep, it will rev extremely high when I have to start it back up. I think that rolling with the engine off is causing some problems with my TPS.....I just don't shut down the motor now until she's under 5 MPH

[popimp]

In my manual it says TOWING THIS VEHICLE BEHIND ANOTHER
VEHICLE (Flat towing with all four wheels on the
ground)
Recreational towing for this vehicle is not recommended.
NOTE: If the vehicle requires towing make sure all four
wheels are off the ground.

Does this mean no EOC for my tranny?

[88HF]

Thats what it appears popimp, or they are covering their ***. If its under warranty maybe it wouldn't matter? As for the E-brake... cars with rear drums almost always use the same drum because its rather simple... but you might have to manually adjust them when they wear too far. If you don't adjust them occasionally, you will be wearing the front brakes more, especially if you are using it often. You can tell when its out of adjustment by how hard/far you can pull up on the lever.

[CO ZX2]

[quote=goodella@hartwick.edu;62930]
One annoying bit is that I hate turning the engine off at night because on my car the lights completely go out until I turn the key back for them. So if a car is coming and I want to power down, I have to flash them. [Edit: By that, I mean the lights are only out for a second] I don't think there's a way around that other than making some switch on the dash route power to the lights regardless of the engine on/off. I think that's fairly unique to Suby's. Anyone try that? [quote]

Sounds like you need an ignition kill switch or better yet an injector kill switch. On most cars, either of these will kill the engine without touching the ignition key and leave on everything else the ignition switch controls. I have read here on GS of this problem but don't recall types of cars, Honda maybe.

[StanleyD]

I might stop using the EOC at higher speeds than. The car is pretty old with 180+k miles and worth under a thousand now, so I wouldn't cry if it died, but at the same time I don't want to be the killer. I don't see a reason to stop EOC in town when coming to a stop with slower speeds (such as coming to a stale green or red).

As for modifying the headlights to stay on, I think I'll just pass. Too much work for something I can live without. I rarely drive at night, so it's not a big issue.

I completely agree with you there. Once in a while I idle coast my 98 Camry, but Im so glad that you started this thread. I was considering a change to EOC every once in a while but now that I know you should NOT let a car with auto-tranny roll, I will avoid EOC. The only time I ever EOC is when Im rolling to a dead apot into a parking spot. I have to turn the car off anyway so I might at well do a ten seconds or so earlier. Now I must make sure that I dont cut off until Im below 20mph. I guess Ive been lucky that I was hesitant to make the change to EOC before. I tried it once on highway and it seemed to work just fine. But I'll never do that again. Only idle coasting from now on. You may have saved my tranny.
I think I have same issue with lights. As soon as I key off I lose lights buts its not big deal to switch back quickly to get back lights, although I end up 'flashing' someone. have you tried only turning key HALFWAY. I havent tried yet but maybe turning key just halfway into ACC instead of OFF will retain your lights. Im dont know as I never thought of that until now.