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View Full Version : Engine-on coasting/P&G with an Echo auto?


Electrify
09-18-2008, 05:57 PM
Hello y'all :)

A few months back I purchased my first car, a 2001 Toyota Echo AT. I picked this car because of its affordable price, fuel economy, and I personally enjoy driving small cars over large ones.

While the fuel economy has been great (30-35MPG, depending if I have the AC on or off), I feel it could and should be doing better. I recently brought it in for a tune up and to fix some problems from the previous owner, but my MPG is still standstill!

I have now been applying numerous hypermiling techniques, and so far it has been okay, but according to the fuel gage (which isn't 100% accurate by any means) I'm only looking at high 30s MPG, at best :( .

Anyways, I was wondering about mild/engine-on neutral tactics. Being an automatic, turning off the engine is not good and it explicitly warns against it in the manual. But when I coast, should I leave it in drive or switch to neutral? I've read numerous comments across the web suggesting that if I keep my foot off the pedal, most auto engines cut off fuel anyways - is this the case with the 01 Echo AT?

Also, could I damage my car by switching from drive to neutral while moving? I don't know what it is, but I enjoy coasting in neutral more, but obviously I don't want to damage my car. Also, I have noticed a few 'bumps' when going from neutral back to drive, what is the best way to address this and could this be damaging my car?

Finally, sometimes I'll coast in neutral to a stop light and apply the breaks while in neutral, gradually of course (am trying to hypermile after all ;) ). So far I have not noticed any issues, but I just want to make sure it is okay.

ksstathead
09-18-2008, 06:21 PM
Gliding means neutral. No fuel cut-off here, but you glide much further. Use this for standard P&G.

Fuel cut-off (DFCO) is another great tool in your arsenal. Here, you leave the car in D and shift gradually down to maintain >~1100 rpm. The ECU detects that you are slowing and cuts fuel to the injectors. The catch is that your engine is still pumping, so it is slowing you down and shortening your distance compared to neutral gliding (NICE-on).

You are correct to avoid FAS (engine off gliding), except for the final small distance to stop lights or your driveway if you want.

So, for P&G, shift to neutral. For the many times when traffic or other conditions put you in a position to need quicker deceleration, use DFCO.

For lurching upon shift back to D, isolate the speeds/rpms when the problem occurs, and very gently press the gas prior to shifting to D to kinda/sorta match the rpm appropriate to the gear you want at your current speed. You need to learn your shift points and rpms for this. Many, including me, don't find great need for rev matching the automatics. Others do so all the time. Depends on car, driver, and situation.

Rome wasn't built in a day. Back off NICE-on gliding in those cases where lurching is a problem until you work up to it from practice in slower speed efforts. A little lurch shouldn't hurt, but it's a relative term, so proceed at your own risk.

Good luck, and welcome!

xcel
09-18-2008, 07:11 PM
Hi Ksstathead:

___Nice reply.

___Good Luck

___Wayne

jimepting
09-18-2008, 08:56 PM
ksstathead had some good advice. I'll add a couple of notes. First, I have an identical car, so have some direct experience. I have a ScanGauge and have done some testing to determine how to optimize some of the variables. First thing I discovered was that increasing the tire pressure up to the max load pressure of 44 psi improved the FE significantly. It was an improvement of about a couple of MPG over the placard pressures.

I also tested various speeds to find the optimum constant speed for the car. My data is misplaced at the moment, but the optimum constant speed for the car was surprisingly low, just over 40 MPH.

NICE-on coasting is my most useful hypermiling driving technique. That makes a significant improvement and does not damage the AT. I also do a small amount of low speed fas 'ing, which hasn't caused any problems in the 30,000 miles or so, but I'm not agressive with that. AND, I obviously don't really know whether it damages the AT, but haven't seen any damage.

Just as a target, I can wring out 40+ mpg in town, and 50+ mpg on the highway - usually at 50 mph. It is a nice little car so enjoy it and work up to the FE techniques.

voodoo22
09-19-2008, 06:58 AM
You cannot go too light on the accelerator. To get a feel for how light you can go on the accelerator speed up to 55 or so then keep backing off the accelerator as little as you can until you slowly start to lose speed back down to 50. You may be surprised at how much lighter you can go on the gas and maintain your speed.

Once you get better with this feeling, you'll become better at driving in hilly areas as well, because you'll have a better feel for how much you need to depress the accelerator going up hill and how much you can back off it going down hill.

You've got a great car here for FE, as you slowly get more disciplined you will see great results.

Electrify
09-19-2008, 04:57 PM
Thanks for all the replies everyone :)

It's good to see I can coast in neutral (you may want to consider putting an article up on that, since Google provides LOTS of results of people claiming otherwise), and I can definitely tell I am pushing up my MPG by doing that. Next week I'm starting as a courier (good to see college paid off...) so I definitely am going to try and get the most out of my gas as possible.

Finally, breaking in neutral is okay too, right? Breaks are NOT ABS for the record.

MT bucket
09-19-2008, 11:47 PM
Yes it is fine, but even better is if you nead to slow down or stop try leaving it in gear and use your ice for braking. It will not use any fuel while doing that, plus save wear on your brakes!

Good luck with your new job, where do you live? I have been a courier for 4 years now in minneapolis. It is hard on fe, but you will get lots of practice :)

lamebums
09-20-2008, 09:03 AM
Hi--

I've never had a chance to drive an Echo with an auto in it but as far as I know coasting in neutral is safe for any automatic provided you rev-match when shifting back into D. There's a few of us on the board who don't trust our cars enough to do that (one guy has a Suburban with 200,000+ miles on it for example).

As you might know already the auto version isn't flat-towable :( but with a proper setup including inflating those tires to the max # on the sidewall you can easily see 40+ within a couple weeks. As others have said Rome wasn't built in a day and it took me nine months to get where I am now and there's probably still room for improvement (Someone like Larry or Sean one of these days is going to goad me into doing something stupid, such as going for a kilotank in the Echo. Which you and I both know is impossible with the goofy gas gauge saying I'm empty after only nine gallons. LOL)

Electrify
09-21-2008, 08:04 PM
Yes it is fine, but even better is if you nead to slow down or stop try leaving it in gear and use your ice for braking. It will not use any fuel while doing that, plus save wear on your brakes!

Good luck with your new job, where do you live? I have been a courier for 4 years now in minneapolis. It is hard on fe, but you will get lots of practice :)

Engine breaking, does that mean shifting it into the lower gears? BTW, I'm actually in the Toronto area, Thornhill to be exact. Though the houses across the street from me back on to the city limits.


I've never had a chance to drive an Echo with an auto in it but as far as I know coasting in neutral is safe for any automatic provided you rev-match when shifting back into D. There's a few of us on the board who don't trust our cars enough to do that (one guy has a Suburban with 200,000+ miles on it for example).

I actually attempted some rev matching earlier on the highway. I got the speed up to 110km/h (limit is 100km/h), shifted to neutral and coasted to 90km/h, then hit the accelerator SLIGHTLY before switching back to drive. The sound on the engine did not sound good. I think it seems better on the engine when switching back to drive, to push a little harder on the accelerator (after shifting) to get it back into proper gear, but I could be wrong. Keep in mind that the AT Echo DOES NOT have a tachometer, so it is hard to rev-match properly.

lamebums
09-21-2008, 09:17 PM
I actually attempted some rev matching earlier on the highway. I got the speed up to 110km/h (limit is 100km/h), shifted to neutral and coasted to 90km/h, then hit the accelerator SLIGHTLY before switching back to drive. The sound on the engine did not sound good. I think it seems better on the engine when switching back to drive, to push a little harder on the accelerator (after shifting) to get it back into proper gear, but I could be wrong. Keep in mind that the AT Echo DOES NOT have a tachometer, so it is hard to rev-match properly.

You'll need to give it some gas to rev-match the Echo--the accelerator pedal isn't the most sensitive out there.

My manual didn't even come with a tachometer--try rev-matching every time I changed gears without one :eek:

Electrify
09-22-2008, 06:58 AM
^^

K, but should I give it gas before or after going from N to D? As I said, it REALLY did not sound too good on the engine when accelerating in neutral, and in fact made the the 'jolt' when switching much worse. Am I doing it wrong, or should I give it the gas after switching from N to D (feels much smoother)?

Sorry for the armature questions, just never have been too much of a car junkie (though now that I have one, that is quickly changing :D )

ksstathead
09-22-2008, 09:14 AM
Without a Scanguage for rpm, rev matching is a challenge. I'd perfect at lower speeds with no rev match and work up to highway speeds. My guess is even your gentle use of gas pedal is too much. At highway speed you should maybe not even hear the engine rev at all. Try with no gas pedal, put it back in D and give it a couple of seconds to synchronize, then ease into the gas.

Don't want you to damage the tranny or break the engine mounts. Consider $150 US for a scanguage?

Electrify
09-22-2008, 04:33 PM
I'm hoping for a Scanguage for Christmas (bonus if it tells me my RPM :D )

Today I did a LOT of driving, since I started my courier job. I was reading a post on here (http://www.cleanmpg.com/forums/showthread.php?t=13708) suggesting some engines do not need to rev-match, and I think I may fall into this category.

When I accelerate after shifting, the bump I feel is more in common with the standard bump you feel when the engine is shifting gears automatically, rather than the large jolt I get from attempting to rev-match.

With that said, some of the advice given here has been great. For example, I try and wait about 1-2 seconds before accelerating, and that seems to help make the change smoother. I also try and ease on the gas, though sometimes I give it a little more pressure, just to get it back into higher gears.

EDIT: I did try earlier this evening to just give it the slightest amount of pressure going from N-D on the highway, and I THINK I was able to get it to shift without the smooth jolt. I can't afford a scanguage right now, but I think I'll try for an add-on tachometer so I rev-match properly (looking at Canadian Tire's website, it costs about as much as a fill up at the pumps these days...)

lamebums
09-29-2008, 09:27 PM
I have now been applying numerous hypermiling techniques, and so far it has been okay, but according to the fuel gage (which isn't 100% accurate by any means) I'm only looking at high 30s MPG, at best :( .

The gas gauge isn't right. From my experience it doesn't move for the first 80 miles.

7/8 at 120-140 miles.
3/4 at 200 miles.
5/8 at 280 miles
1/2 at 320 miles
3/8 at 400 miles
1/4 at 500 miles
1/8 at 580 miles

Or something like that, I will never quite get the gas gauge in the Echo. It moves quickly on one day, and then doesn't move for the next three. And the intervals aren't equal.





And yes the Scangauge tells RPM :)



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