100+ hypermiling / ecodriving tips & tactics

[Vekke]

I am sure that this works at least in Finland.

In Finland these light sensor lights are in places where usually is less traffic, but the road is still quite big. So when you are coming to this kind of junktions, all the lights are red and this is the easiest way to recognice this kind of junktions. If you have extra long pair of head lights this works extremely well.

It is a nice feeling when you get the first green when you are still in motion and the other guy will have to wait. Even if the other car was nearer the lights in closing phase, but you ordered the green 100 meters before the lights just because you flinked

In Finland Buses and etc. have these IR type remote controllers, by which they can send signal to the lights that they are coming towards the lights. Depending on the situation lights will be green longer if the bus is on the green lane. If the bus is on the other light the green will be much shorter than normally.

Near firedepartments lights can be controlled from remote control centrals. So usually they put the lights to flink yellow. Of course this depends on the city size and traffic conditions, in heavy traffic this is not possible. In these cituation they try put the lights to green when firetruck is near the lights.

I have to mention that 20-30 % ( my estimation) percent of the lights are timed also here in Finland. So the ligths will turn in certain pattern with or without cars. This is very frustraging if you are the only car in the lights and it takes over one minute to get the green.

[Brillig]

Suggested Tips (I live in Alabama!):

In Summer, leave windows open slightly when parked to allow hot cabin air out (less AC)

Use a reflective window shade/sunscreen when parked.

Light colored car seems to be cooler in summer (car choice when buying).

At slow speeds, windows down, AC off - at higher speeds, windows up, AC on.

Fuel up in the morning, and drive off the top half of the tank (less evaporation, and 'gunk' in bottom half of tank does not get sucked into engine)

[Brillig]

[QUOTE=Tango Charlie ... Never Downshift [/QUOTE]

Engine braking burns fuel to slow the car - and introduces wear etc, generally a bad idea when

cost ( fuel + engine wear ) >> cost ( brake pads ).

[KJSatz]

Often, engine braking (in gear, above maybe 1000rpm, operating temperature, foot off the gas) turns fuel injectors off. If you do a gentle downshift, not to absurd rpm and with a good revmatch and smooth release, you're good. Many automatic transmissions automatically engine brake...if it were so bad, surely they would just shift into neutral whenever you stepped on the brake (though that would be cool, to have easy access to neutral in an automatic).

[noxman]

Halo !
I'm very confused with those tips n. 44:

44) The most efficient way to slow down

When you *have* to slow down, here's an approximate heirarchy of methods, from best to worst.

1) coasting in neutral, engine off (ie. roll to a stop);
2) coasting in neutral, engine idling;
3) regenerative coasting (hybrid vehicles)
4) regenerative braking (hybrid vehicles)
5) coasting in "deceleration fuel cut-off" mode (in gear, above a certain engine RPM)
6) conventional friction braking (non-hybrid or hybrid)


Based on my scan gauge is better choice n. 5 ( with 0 consumption)
After is n. 2 (coasting in neutral, engine idling)

Can somebody explain me, why coasting in neutral is better than fuel cut-off mode in high gear?

Thank you.

[jtgh]

your are correct , many cars use almost no fuel at all in cut fuel (decel mode)

i too have watched fuel calcs in this mode, cut fuel.
and mpg goes near infinity. 1500 mpg on some cars. ( full scan tool with logger , set to mpg and fuel injection Grams/min.

depends on year, and car make and ECU.

My Miata cuts almost all fuel. course it slows car so that is a factor.
but not in 5th gear, 5th just barely slows car and in fact keeps me at near speed limit. Kinda perfect in fact. holds me legal, and cuts fuel.
what more you want? egg in beer, heheheheheh

coasting is both illegal and dangerous, but few here care, it seams.
out of gear.

I used to coast down Grape Vine Hill , long ago and hit over 85. (1970)
with wind behind, upper limit is unknown, real scary. place.
Seen campers blow clear off the road there. (even going up hill at 50)

[McTimson]

Coasting in gear uses no gas, but it also slows you down faster than coasting in neutral. So, if you have to stop fairly quickly, then coasting in gear is the obvious choice. Or, if you're going downhill, and the car can keep its' speed while still in gear. But, if you plan the stop, and have a long way to go until the stop sign, then coasting in neutral will be better overall, since you'll be able to let off the gas earlier than you would if you kept it in gear.

What you don't want to do is coast in gear, and then find out that you're going too slow to make it to the stop, because then you'll have to accelerate again, which will pretty much defeat the point of coasting to the stop.

[noxman]

Thank you for reply.
From another man i have read, that in cut-off mode still little fuel be consuming.
Bc show 0 consumption, because is connected to main sensor.
Secondary sensor uses little fuel. I don't know if is true ?

[jtgh]

the OBD2 dont lie, it shows actual fuel used, period.
just look. I use palmer software. you can plot it to your hearts content.
it can do the math real time or after you get home. any why you want.

on some cars the compression is really high and the throttle plate is closed fully at decel.
so they open the ISC to let in a letter air. (ECU code)
so this too can very , car to car model and year.

do not do real coasting , and worse engine off ,until you are sure the ignition will not go to lock, I know one friend that drove offroad , on freeway doing that stunt. car was totaled. Him ok. IGNITION LOCKS are DANGEROUS. (not in operators manual)

on old cars cut fuel leaks a little gas to keep CATCON lite off.
on newer cars it is heated and cut fuel , cuts way more fuel than idle consumption.
Check it out?

you can test this theory
drive down hill X
log data in decel mode , coasting in gear, and out of gear.
repeat same hill , same speed , neutral with motor off ( find a safe way to do it)

now examine your logs.

end mystery.


Running good OBD2 software, the kind that shows real fuel consumed in all modes is important.


some Cars will not allow you to capture real time injector pulse width.
for those cars I use a scope. (DSO is best)
attached to the injector you can watch the real thing. Nothing better.


federal OBD basics dont alllow that , you need extended diagnostics for that.
MOST Off the shelf device readings:
the MPG and the like are actually , just MAF/vss derived.

eg: (typ. code)
Hear are the steps to make the conversion:

1. Divide the MAF by 14.7 to get grams of fuel per second
2. Divide result by 454 to get Lbs fuel per second
3. Divide result by 6.701 Gals fuel per second
4. Multiply result by 3600 to get gallons per hour

The expression for GPH is: MAF * 0.0805
To calculate MPG divide the MPH by GPH.
The final expression for MPG will be: VSS * 7.718 (speedo scaling, is crude)


those scan guage readings are mostly bunk.

ok , in closed loop, never ok , coasting.

IMHO.

BEFORE assuming, take real measurements ,directly and compare.
trust me...

[PaleMelanesian]

You're missing the point here. Sure, INSTANT fuel consumption is lower under DFCO, but the average for a trip will end up worse, because you have to burn more fuel later to make up the lost speed due to the engine braking.