I did the unthinkable today... EOC
 

I've been a firm advocate of not needing EOC for better fuel economy for a very long time... but I just had to try it today.

The car already doesn't have power steering, and I bump started it without any notice at all.

Just sayin... I liked it.

Matt -

Heh heh heh. That's what makes older cars so fun. The good old days.

CarloSW2

When will you shell out for the mid?

probably going to be a Xmas present for myself... or a birthday present.

So like in a month.

I am mixed on EOC... looking at it in a totally technical way, I have trouble accepting that it should contribute to our overall FE. That being said, I use EOC all the time, and it definitely boosts my numbers to levels that would be totally unattainable without it. Definitely one of the best tricks in the hypermiling bag. It was a bit scary at first, but now I actually like the feeling of it. I feel more in tune with the car.

EOC basically means free mileage, so I plan to continue using it until something makes it obsolete...

Keep it up, and keep it safe. Getting in a wreck while using this technique would kinda defeat the whole purpose..

i EOC only when ending a trip. ie last stretch home, to a parking spot,etc.
don't have many opportunities other than that here. anyway, not sure there's enough evidence to disprove wear on the tranny and starter in ATs to restart especially while still moving.

In the automatic, I was always worried about the "stranded" factor if the starter fails. The starter itself can be refreshed for a couple bucks and some elbow grease, so it wasn't the expense. That concern can be addressed with a replacement schedule (rebuild one starter while using the other) however.

With a stick shift it has been a no-brainer. If the starter quits, bump start it. Folks get into spending gas on speed matching and whatnot, I don't worry about it, there's always a better ratio trans waiting for me in the boneyard anyway if I am killing it ;) And there have been a few folks who have EOCd since new with many miles and no issues to report.

I absolutely love EOC. I do it every chance I get on my commute (which is often). I would say I EOC for at least 10% of my daily commute (I'm being conservative on this guess as I haven't calculated it). The ONLY two FE mods I'm really using are an HF transmission and EOC.

Welcome to the smoother, quieter side of life Matt.

BTW - When EOC'ing up to a light, I often think "this is what it would be like to be in an EV" as far as noise level goes.

I have just begun as well, using COX2s injector cutoff switch method ( a breeze to setup in the mazda3) allows me to do it without messing with the key - keeping SG running and my cell phone charging. Passengers dont even notice what Im doing! I have found that my power steering remains even in EOC through injector kill switch. My brakes are good too, although I admit that I havnt used them enough during EOC to determine how many applications I have before the boost is out - but I havnt lost them yet.

Thanks to you guys here, I have learned how to bump start smoothly (double clutch or whatever you want to call it). Before that it was a rough jerk that I didnt like and wasnt going to do for long. But now - Like DaX - I do it every chance I get.

I have found with the fuel cutoff in gear coasting (uses 0 fuel supposedly), I coast in gear to stoplights when I know I have to slow down anyway and then stop. I EOC when coasting down hills and such that require maintaining speed on the other side.

I do have a question though. How does fuel cutoff in gear coasting work? How does the engine stay running if there is no fuel injected - or is it so minuscule that it keeps the engine running but not enough to be calculated. I mean whats the difference between the computer cutting the fuel during an in gear coast, and me cutting the fuel in an EOC?

Answering my own question......is it because in gear coasting keeps the engine running by virtue of the drivetrain continuing to turn the motor, while in EOC, motor stops turning?

Thanks.
-Jeff

From what I've learned "DFCO" cuts off fuel until your RPMs are at a lower level like 1000 rpm but that number varies epending on what you're driving.

It works because the wheels are able to keep the motor running. Instead of the motor running and moving the wheels, it works vice versa.

EOC is a great way to boost Fe, but it is dangerous and illegal in most states. My brake pedal goes stiff after a half a minute of so when using the brake while coasting down a hill. Some hills around new england are quite long and steep and without using the brake you could easily get up to speeds of excess of 80 mph plus, and I don't feel comfortable at that speed with a stiff brake pedal. I say nay to EOC.

BTW it is "don't taze me dudebro."

does EOC count if your coasting down a hill and the car only idles at 100-200 rpm? :D i dunno what causes that but i like it. scary part is that it runs as smooth as if it were at 800 rpm...yet its eerily quiet

DaX -

Segway .... My Dad was looking over my shoulder and he identified your Avatar, North American Aviation! I've been scratching my head for months over that!

CarloSW2

Wow, that's awesome.

My only thing about EOC is that I always end up having to go up a hill after the coast, and I don't know at what point to start accelerating again for the hill. Because if I wait too long to go back in gear I will waste gas going up the hill because I won't have enough momentum for it.

slimreynolds -

Yes, I look at EOC and all other GasSaving strategies as context driven. My rule of thumb for EOC is that I get one solid brake pump (no multi-pumps). After I use that, I do a bump start. I also keep it to the straights because I don't have manual steering (on the infinite to-do list). If I had the skillzzz, I would attach another vacuum canister on my car to increase the duration of my power brake pressure (CO ZX2 and others have spoken of this).

Only you know your road, so only you know what will work for you.

YRMV (Your Route May Vary),

CarloSW2

Not true. Unless you are in a semi, you can coast in gear but with the clutch disengaged, though I'd reccomend a different strategy for talking your way out of such a ticket. However speeding and tailgating are illegal but no-one seems to mention that?!? Must be really biased against EOC or something to keep seeing this misinformation keep cropping up. Maybe it is a case of "waaah, that sounds too much like work, let's just poo poo it".

And it is only as dangerous as the driver, the brakes are firmer when boost runs out, but I can still lock them up when the boost is gone (and/or downshift and/or use the handbrake). It is just a matter of practice (away from real cars please, you are basically learning to drive again)

Standard Disclaimers Apply:
https://www.gassavers.org/showthread.php?p=38813

hah yea thats the way with me on a cetian long exit ramp. can coast for about a 1/4 mile then theres this hump and a slight grade at the bottom. after coasting your around 55 at th ebottom but the hump knocks it down to like 45 then it seems as if you jamming on the gas to get up to 55 again cuz of the slight grade

yea hes right about the coasting in gear. i just wanan know how the cop knows if you were in gear or in neutral...:confused:

some cars you cant overcome the no pressure (takes a crapload of force to stop my truck with the booster empty) thers no way i could lock the wheels. the handbrake only locks the rearwheels which any slight turn of the front wheels is gonan put you into a skid/spin. that and it takes up to 30 meters to stop the adverage car from 30 mph. with only ther handbrake(longer if wet). thats only true if it works and the cables dont snap.:D

while it may be true for some cars, not all cars are equal....

Well a simple vacuum pump and vacuum switch can fix that if you don't feel safe stopping the car without assist. A larger vacuum volume can buy you more time but I would reccomend the electric vacuum pump if your car NEEDS vacuum to stop.

The pump only needs to kick in when the vacuum gets too low, then it can shut off.

It takes a lot for me to eoc right now. It's just too hard to pull off in busy traffic with an automatic tranny. But if I know it is going to be a lot of slow traffic on a slight downgrade I will kill the car and coast. One time I had a multi light delay on a downhill. I had the engine off for almost 10min.

What's illegal? Being in neutral or leaving it in gear but putting in the clutch? Do you have any links?

Edit, here is a link that demonstrates there is a difference:
https://www.gassavers.org/showthread.php?p=69148#20

I NEVER coast in neutral. Of course sometimes I shift a bit slowly. ;)

Driving in gear with the clutch pedal down is supposedly bad for the clutch.
I don't know the exact mechanics but the designers expect the pedal to be down only briefly - not as a steady state thing.

As for legality, I suspect it's illegal in most states - but who's to know? Just don't be doing 30 where everyone else is doing 50. And don't let it buck when you bump start.

I rarely EOC my car since it's an auto tranny. Sometimes I'll EOC to a long red light or when pulling to a stop at a gas station or some such. In my car, starter replacement is a real PITA so I don't want to be key-starting it all the time.

I do like the simplicity of my 83 Tercel. It apparently does have power steering, but I had to bump start the car in a corner to confirm that one. It really doesn't even need it. I'm now strongly considering removing that belt. Even the brake vacuum assist seems superfluous.

It places extra pressure and wear on the throwout bearing.

Yah, if it is legal, or unenforcable, where you live you'd be better off in neutral.

If you really want to make the roads safer, focus on cell phone users, supposedly talking and driving is as dangerous as DUI:
https://www.wired.com/culture/lifesty.../2006/06/71288

I tried some EOC in my VX lately. After seeing my mileage drop to 42 mpg on this last tank, even with using the shift-light, I think the cold temperature have given me a reason to EOC more.

Carlos,

You could have asked, I'm not that secretive and devious! :D

Same here, and if I can find a "potential energy" parking spot I'll also coast out... at one location I visit weekly, I can leave the parking lot and roll up to the stop sign at the corner, wait for a break in traffic, and then start the engine and go.

Having an automatic, I don't want to risk anything beyond 10, 20, etc. feet. At first I was lamenting not being able to play with EOC, but realistically it would only make a tiny improvement in my numbers. Here's my thinking:

The VW idles at 0.3GPH. Let's say I can manage to NICE-ON coast 1/3rd of my driving time (insanely optimistic, but just for easy numbers). That means I would burn one tenth of a gallon of gas per hour while I'm coasting in neutral with the engine on. That, minus the (admittedly small) amount of fuel needed for restarts and re-topping the battery from running the starter, is absolutely the most I can expect to benefit from EOC. And realistically, the number's probably half or a quarter of that.

In other words, it seems to me that simple NICE-ON coasting gets you most of the benefit, and EOC is incremental. Granted, we all know that a bunch of small increments add up and every tenth or hundredth of a gallon matters... I'm just sayin'.

Sadly, I can't verify the above because of the VW's auto tranny... and if anyone sees anything wrong with my logic, please speak up.

Rick

Engine On for Me
 

I have to agree. Even with a manual transmission, I figure that the clutch and/or starter wear will probably catch up with me if I do that stuff so frequently. The rate of idle burn is so low as to be almost negligible.
I can (and do) neutral coast in a few areas that are in the 40-50 mph range. I avoid it on the interstates, mostly, because of the traffic changing around me and the awkwardness of speed matching the engine beore clutch re-engagement as I pick things up again. That, and the fact that we don't have any grades that can last me more than 3/4 of a mile anyway :( .
My car cuts off the injectors until the engine speed drops to ~1200 rpm so I can benefit from leaving things engaged, putting up with a little pumping loss drag.
I also question the wisdom of interrupting the oxygen sensing/fuel control loop by shutting the engine off then starting up again. It can cope with idling and coasting but I wonder how long it takes after startup before it's thinking clearly again :) .

DaX -

I know, but the thought of Google not knowing what NAA stood for kind of put me in an existential crisis for awhile. I was thinking, maybe I'm not meant to know, :eek: :D ;) .

CarloSW2

I keep www.acronymfinder.com in my arsenal of search bookmarks.

I think the oxygen sensor issue is a minor one. With an already warmed up engine, base fuel mapping for open-loop operation is already leaned out. The oxygen sensor is just there for the fine tune.

Bottom line for me is that I don't EOC usually unless I anticipate being able to go 1/4 mile or more before restart.

are there any lube(lack there of) implications w/EOC specifically w/ auto trannies? i keep forgetting to put the car in N BEFORE shutting down.:mad:

Enh, for short periods with no load it probably isn't an issue, but if your car can be flat towed behind an rv (like s-series saturns) then it should be no problem.