Ways to save fuel.

[91nbtsi]

2. Do Not Accelerate or Brake Hard. By anticipating the traffic and applying slow steady acceleration and braking, fuel economy may increase by as much as 20%.

WTF does braking hard have to do with using gas?

Because when your engine is doing the braking, it will shut off the injectors completely, thus saving more fuel than just slamming the brakes on.

[Kracka]

Slow grandma-style acceleration consumes more fuel than a moderate rapid acceleration to cruising speed.

[Halon]

I've also heard that at hwy speeds, you are better off using AC rather then having your windows down. Apparently having the windows down at that speed causes a ton of drag and actually makes you get worse milage then just having them up and the AC on. Anyone else heard this?

[AJ]

I've also heard that at hwy speeds, you are better off using AC rather then having your windows down. Apparently having the windows down at that speed causes a ton of drag and actually makes you get worse milage then just having them up and the AC on. Anyone else heard this?

Mythbusters did an episode on this. I can't remember which way it went though.

[91nbtsi]

I've also heard that at hwy speeds, you are better off using AC rather then having your windows down. Apparently having the windows down at that speed causes a ton of drag and actually makes you get worse milage then just having them up and the AC on. Anyone else heard this?

That would probably depend on the aerodynamics of the car you are driving. If when you open the windows it becomes a giant wind-sock, then you probably are better off using the air. Otherwise, the A/C compressor obviously takes power/energy to rotate and compress the refrigerant. Doesn't really matter to me, as long as I have A/C that works, I am going to use it!!

[StealthGST]

Mythbusters did an episode on this. I can't remember which way it went though.

The bullshit ford computer monitoring said that it was more fuel efficient to run the A/C, but in reality it was worse to drive with the A/C on over driving with the windows down.

[StealthGST]

That would probably depend on the aerodynamics of the car you are driving. If when you open the windows it becomes a giant wind-sock, then you probably are better off using the air. Otherwise, the A/C compressor obviously takes power/energy to rotate and compress the refrigerant. Doesn't really matter to me, as long as I have A/C that works, I am going to use it!!

I was going to say this... My eclipse barely flows any air in with the windows down at highway speed, whereas my 1996 Ciera is terrible, it blasts your head back into the seat.

[Goat Blower]

Because when your engine is doing the braking, it will shut off the injectors completely, thus saving more fuel than just slamming the brakes on.
If your injectors shut off completely, your engine would stall. And letting off the gas using the engine for braking is the same as using your brakes since your taking your foot off the gas and applying it to the brake. Except for those two-footed drivers out there.

I'd venture to say it's probably crap, but if it has any merit, it'd be more from gradually letting off the gas allowing a smooth transition for the ECU signal to the injectors and the injectors themselves. Snapping your foot off the gas quickly causes the ECU to quickly make up for the throttle plate shutting and a vacuum caused from this in the intake manifold for a few milliseconds. The resulting back up in pressure throws off the mass air sensor causing a quick blip from the injectors. This is of course speculation as I'd guess you'd save about $.20 a month in gas from actually doing this.

A few to add: tape all your body seams with Honda tape and remove your antenna and door mirrors. All the aerodynamic drag can really cause havoc with your 20mpg DSM. :D

[Shane@DBPerformance]

If your injectors shut off completely, your engine would stall.


They come back on at 1500RPMs or whatever RPM your ECU is programmed to come back by alive after decel fuel cut.

[91nbtsi]

If your injectors shut off completely, your engine would stall. And letting off the gas using the engine for braking is the same as using your brakes since your taking your foot off the gas and applying it to the brake. Except for those two-footed drivers out there.


Um, they shut off completely. As Shane said, they come back on at whatever rpm your decel fuel is set to shutoff, be it in your stock ecu or whatever you use.

Just because you let off the gas doesn't mean you have to step on the brakes, does it? haha. If you let the engine do more of the braking, before you hit the brakes, it will save a small amount of fuel each time..not saying you are even going to notice, but it will.