New HyperMiler. (EOC) Engine Off Coasting

[A_FITZ]

Ok.

New to the website. Real glad I found it..

Anyway, ive been doing this EOC thing allot.

I drive a 93 Nissan Maxima - Automatic. V6 - 3.0L

Downhill is where I find EOC to be the most effective.. sometimes I could make a whole stretch if I could accelerate to a good speed, then EOC for a long time.

Is this boosting my MPG.. and is this a good thing to do with an automatic car?


I was thinking of doing crazy things, even duck tape airpockets that shouldn't be there because if they didn't exist, my car would be more aerodynamic.



So far to boost my MPG, ive been going no faster then
65MPH. Ive been EOCing.., and sometimes putting the car in Neutral at stops, even shutting the car off if I think ill have a good enough time to just sit and do nothing.



Im looking to get a 250cc Ninja in the future and eco mod the hell out of that.., but for now, im stuck forced to only using the car option right now. The V6 gas sucking nature of your income option.

Thank you.

-Alex Fitz

[SentraSE-R]

You shouldn't be turning your engine off during high speed glides with most automatic transmissions, and that includes all Nissan automatics, if my memory serves me right. Only do it if your car is flat-towable with the driving wheels on the ground. Otherwise you're getting no lubrication, and you're risking major transmission damage.

[luvit]

what about engine on coasting in neutral? -- i have an automatic.
i've been doing less of it. i don't have many opportunities to do it.

from my tests, i'm not gaining much more than 1mpg. (i've found another tactic that i'd like to share in a thread tonight).

[SentraSE-R]

Engine on isn't a problem, AFAIK.

Neutral coast to all stops until speed drops <20 mph. Turn engine off if you're going to be sitting there >7 seconds. P&G (or at least G) down hills. Keep engine <2000 rpm and encourage upshifts early. That's what works for me with an AT car.

[womprat]

!! This is especially bad for nissan automatics. SentraSE-R is dead right. I've been told by Nissan service people that rolling in neutral any length of time will damage the transaxle and this goes for all of their models, not just the FWD V6's. With the engine on, lubrication is still flowing so this is not harmful, but that said many transaxles are not designed for this, and some will still be damaged.

If your really gutsy short coast downs might not do much harm, but I'd err on the side of caution.

I was told, if you really must tow the car with engine off you can only do this for a short distance and low speed before the engine needs to run for a while again.

I have essientially the same car, but it was badged different for sale in eastern markets. Engine is a Nissan VQ, but a 2.5 with a variable intake manifold, instead of a 3.0 V6, these engines have pretty good ECUs, you'll find the injectors cut out when your decelerating off throttle (at speed, or above something like 900rpm, and when the engine is warmed up). It's because of this I've found that coasting in neutral with engine on is little benefit, because the engine is back to using fuel at idle speed. There may be cases downhill where you gain some mommentum you wouldn't have with engine braking.

Oh and from experience, I'm not a fan of EOC in Nissan Maximas, without the power brakes they are a little scary to get them to pull up. :S ... Is EOC for flatlanders?

It's quite easy to take advantage of the fuel cut with a pulse and glide technique with these cars, fully lifting off the throttle.

[99metro]

Ditto on not EOCing with your automatic. Neutral coast all you want (NICE-ON), and I agree with coasting down to <20 mph to stop signs before hitting the brakes. It takes practice with that. Also you can keep the tranny in neutral at stops until the light changes or it is time to go, then click to Drive. You use more horsepower in Drive while stopped than you will in neutral.

[A_FITZ]

@99Metro - Yeah I read that basically with your car in drive..., and you holding the brake, your engines still kickin in to go but your brakes are holding you back..

Thus pointless, so go neutral until green again or you have to go. I mean..hey I guess thats the way cars are made though..older cars.

__@womprat -__ So your saying..I could probably get the same benefit without EOCing, just by letting off the gas?

Idk.., I mean, I went downhill from my exit, accelerated to 45, and with the engine off (Engine Off Coasting), I went like far..because its downhill. I went really damn far without even having the car on. Even made a right turn into an establishment, AND parked! Never even had to turn the car back on until I came out of the store!



@ Everyone

Now...., I found the only way I can get better MPG is by EOCing and Neutral Techniques. I drive a V6 Premium Fuel sucking 93 Nissan Maxima, which is a ****in powerhouse and runs like a champion and burns mustangs. Yes, burns mustangs.

But, with these 2 MPG boost techinques.., am I damaging my cars longevity in the long run...? Or on the brightful hope side.. helping it?

-A_FITZ

[SentraSE-R]

If you're NICE coasting v. EOC, you burn about .25 gal/hr. In a 1 minute NICE coast, that's .25/60, or .0042 gal. you consume. Let's say you were getting 25 mpg for a 25 mile drive, and coasted one last mile into your driveway. You consumed exactly one gallon on your drive until the coast. I know you're not coasting at 60 mph, but let's use that 1 minute NICE coast, and assume it's a mile, just for argument's sake.

EOC, you use no fuel, and get 26 mpg.

NICE-on, you use 1.0042 gal to go the 26 miles, and get 25.89 mpg. It's a lot closer to 26 mpg than to 25 mpg - really almost unmeasurable.

[womprat]

Originally Posted by A_FITZ

__@womprat -__ So your saying..I could probably get the same benefit without EOCing, just by letting off the gas?
-A_FITZ

Well, I'm saying good pulse and glide taking advantage of your Max's built-in fuel cut out will be almost as good. Big long EOC's like you mention will save you alot of gas, than just lifting off as part of P&G.

I find it really hard to squeeze the last bit of economy out of a nissan V6, it's the price you pay for having the ability to embarass bigger more expensive cars. I've got to work on some aero mods.

Hot tip: I think max's are one car that exhaust mods help economy - theres a nasty restrictive bend in the y-pipe. Known for 10%-15% power right there, and some say a little MPG - as long as rest of exhaust is standard.

Anyway here's the official information from Nissan on the transaxle issue:

FLAT TOWING OF NISSAN VEHICLES
This bulletin amends NTB99-020b. This version includes additional Model and Model Year application.
Please discard all paper copies of the earlier bulletin.
APPLIED VEHICLES:
All Models
1992-2004
SERVICE INFORMATION
This Bulletin contains guidelines for towing Nissan vehicles with all four wheels on the
ground (sometimes called "flat towing"). Customers sometimes use this method when
towing the vehicle behind a recreational vehicle, such as a motor home.
• Failure to follow the guidelines in this bulletin can result in severe transmission/transaxle
Automatic Transmission/Transaxle Vehicles
MODEL
MPH/DISTANCE
All Nissan
Flat Towing will damage internal transmission parts.
(Including
(see notes below)
Murano CVT)
• DO NOT tow any automatic transmission/transaxle Nissan vehicle with all four
wheels on the ground (flat towing). Doing so WILL DAMAGE internal
transmission/transaxle parts due to lack of lubrication (the
transmission/transaxle oil pump only operates while the engine is running).
• For "emergency towing" procedures refer to the limited MPH / distance
procedures as outlined in the vehicle’s Owners Manual.
• Never flat tow a manual transmission/transaxle Nissan vehicle backwards, but
To tow a vehicle equipped with an automatic transmission/transaxle, an appropriate vehicle
dolly MUST be placed under the towed vehicle’s drive wheels. Always follow the dolly
manufacturer’s recommendations when using their product.
Manual Transmission/Transaxle Vehicle Towing Guidelines
MODEL
MPH/DISTANCE
All Nissan
60 mph / 500 miles (see notes below)
Always tow with the manual transmission/transaxle in Neutral.
On 4WD vehicles, place the transfer case in the 2 HI range
(failure to do so will cause the powertrain to bind up).
After towing 500 miles, start and idle the engine with the transmission/transaxle in
Neutral for two minutes. Failure to idle the engine after every 500 miles of towing may
cause damage to the transmission/transaxle internal parts"

Yikes. Engine on or nothing in the case of the Auto.

source: http://maxima.theowensfamily.com/tsb/NTB99-020c.pdf

[A_FITZ]

Ok, thank you SentraSE-R and womprat.

That really cleared up my knowledge on my car for EOCing

Basically, I got mainly from SentraSE-R

((Nissan Maxima - RPMS already drop anyway low when you step off the gas pedal..))

Basically what I got from womprat

((Nissan Transaxle can possibly be damaged from this, as Nissan officially explains NOT to TOW vehicles in neutral on all 4 wheels, or it could damage something. Basically, Nissan Maximas arent the greatest ..or slight to closest best vehicle for EOCing.))