Safeway Gas

[w squared]

I thought coasting down a hill in gear uses zero gas if you have a modernish engine

One question...if your engine is running, how does that happen without burning any gas?

You may be confusing hybrids with regular vehicles.

[Immortal]

Shows what you know not true again, my best fuel economy is in reverse

Well compared to your 181L/100kms in forward, ANYTHING is better!

[Chupacabra]

Not true. My best fuel economy invariably occurs when I select "Mexican Overdrive".

This totally explains why my dad drives this way... and all my cousins down in Mexico....

But ditto with my JK, been averaging between 14-15l/100km this winter, in summer when I first drove it off the lot I was getting  about 10.9l/100km

As for this whole higher revs = more efficient speak... It is true that an engine wastes less gas and burns it more quickly at higher revs, they simply operate better. However, the lower the revs, the less fuel you use. This simply means that the engine isnt going to be burning the fuel passing through it as fully at low revs as it would at high revs.... but is still using less fuel, just using that fuel "less efficiently".

Best thing for mileage is drive like you had a glass of water on your dash trying not to spill it. No hard accelerating or braking. Look far ahead to plan your starts and stops. Nothing burns more fuel than taking off from a standstill.

[The Machinist]

Your fuel milage is not based on the rpm of your engine.  More so on how much fuel you have to give the engine to make it do what you want.  If you are driving everywhere at low rpm's you have to give your engine more gas to make enough power.  If you drive around at an rpm where your engine is making good power you don't need to give it much gas to keep you moving.

[JackstandJohnny]

Your fuel milage is not based on the rpm of your engine.  More so on how much fuel you have to give the engine to make it do what you want.  If you are driving everywhere at low rpm's you have to give your engine more gas to make enough power.  If you drive around at an rpm where your engine is making good power you don't need to give it much gas to keep you moving.

this is so true......  and its why (back in the day when we had a stock TJ) it got worse mileage on the highway at 2100rpm than my Brick/YJ at 2600 rpm.......

its also the same reason i laugh at people that 'accelerate slowly' to save fuel;  the whole time you are doin gthis, your engine is working harder as its lower in the RPM range, and your dumping more fuel into the mixture: then when you finally get into the powerband, it shifts out..... and you play the same game.

accelerate off the line, get up to speed and coast............. you'll see the same, if not better gas mileage, and you won't squirt poeple off that are stuck behind you   funny thing i noticed in the JK;  if you are coasting, it lights up the 'eco' mode in the dash. this usually comes on under 2000rpm;  howver, if the engines struggleing, its off;  when accelerating, it never says 'eco' mode.......  no matter what the RPM. it only hits 'eco' when coasting. so i accelerate to speed, then coast........ works the best.

[Jrama]

One question...if your engine is running, how does that happen without burning any gas?

You may be confusing hybrids with regular vehicles.

Nope,  the computer is smart enough to  cut the gas and let the engine run on momentum. I have heard this from numerous sources, we also had an audi that would display zero fuel usage coasting down hill in gear. Now I'm not sure if a tj engine is this smart, but maybe the JK's are?

Me confuse a hybrid with a regular vehicle...never....

[w squared]

It may "display" zero fuel usage...and you may have "heard it" from a few sources...but then again I've heard from sources that high zinc oil and belt dressing will cure the clap, and the computer in Silverfox's JK displays some VERY interesting fuel economy figures. Just ask him about it 

If you stick your nose in front of your tailpipe when your engine is running and in neutral, you will find that there is indeed fuel being burned, and thus there is a lovely exhaust smell. The same applies when coasting downhill with a non-hybrid vehicle. I will certainly agree that you're not buring much fuel...but there is still fuel flowing into the engine. I would be rather surprised if a non-hybrid actually shuts down the fuel flow while the engine is running (regardless of whether or not it's in gear). If it were to do that, what's going to happen when you get to the bottom of the hill?

[Immortal]

Or, Todd, you can also prove this by starting your engine, placing the vehicle in PARK, and walking away..... You then return several hours later, and check your fuel guage. If that doesn't work, you have obviously not given the engine  time to burn enough fuel to move the guage. Come back tomorrow.

This is fast progressing into a "How do I get better mileage out of my Jeep?" topic.
For all of you that are about to ask.... YOU DON'T! BUY A FU@&ING CIVIC!!!!

[Knox]

But I don't want a civic...

[Justink]

I don't remember the km's/litre on my jeep but it was 9-11 mpg.  It sucked!!  I was spending 600+ a month to drive to school and around town.  Bought a sunfire and I get 30 mpg driving the same way I drove the jeep, pays itself off in about 5 months.  I will admit it  I do miss the jeep though  

[TL-Iguana]

If you stick your nose in front of your tailpipe when your engine is running and in neutral, you will find that there is indeed fuel being burned, and thus there is a lovely exhaust smell.

For those that are not willing to kneel down on the slushy roads here Im sure you can also post in the WTB section for a length of rubber hose, and then run that into the cab with the windows closed... It will perhaps solve your fuel economy issues, and keep posts like this down to 3 pages, instead of 8 like the other one!

Trevor perhaps said it best -

This is fast progressing into a "How do I get better mileage out of my Jeep?" topic.
For all of you that are about to ask.... YOU DON'T! BUY A FU@&ING CIVIC!!!!

[YoungFluff03TJ]

 I was spending 600+ a month to drive to school and around town.  

What the....like 600 dollars...canadian dollars? a month? do you live in america and drive here every day?

Anyway my question was answered about 20 posts ago...in case...anyone was still wondering....