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I don't cut my engine off, neither do I really plan too but I am looking for some other techniques that some of you people might be using that I might not.
Does anyone have some links for hypermiling in a stick shift without cutting the engine?

Also, could someone tell me at which point it is more beneficial for me to just drive in gear and versus coasting in neutral. eg. Does Coasting in my neighborhood at like 10 an hour trying to squeeze in as much coasting as possible make sense or should I just slowly speed up again and maintain. I am looking at this at a distance versus time kind of thing.

I already get between 38 and 42 mpg in my 2007 Rabbit so I am just looking a for a few more techniques to squeeze a few more miles out.

Thanks

Mike

Have you read this yet? http://www.cleanmpg.com/forums/showthread.php?t=1510

Coasting with the engine running and the transmission in N at 10mph is most likely not going to be favorable. To find out, you'll need a scangauge or something else that can tell you fuel used at idle and in gear at your chosen speed. In my Elantra the cut over to no benefit seems to occur not far under 20mph. I haven't checked it in the Insight.

I have already checked into all those options and links thanks guys, that is why I am asking if there is anything new out there.

Coasting with the engine running and the transmission in N at 10mph is most likely not going to be favorable. To find out, you'll need a scangauge or something else that can tell you fuel used at idle and in gear at your chosen speed. In my Elantra the cut over to no benefit seems to occur not far under 20mph. I haven't checked it in the Insight.

Thanks, that does help a lot!!

My experience matches Sean's. Coasting at highway speeds with engine on (NICE-on) doesn't cost you much mpg v. EOC. Coasting NICE-on at 20 mph and less does cost you.

They are very correct about NICE-on coasting being dependant on your speed.

The Ranger idles at .24 gph (when warmed up), and many vehicles on here are about the same.
As a rough guide:
speed times 4 equals current mpg...
So 55 mph would be 220 mpg, but 10 mph would only be 40 mpg.

Keeping that in mind, I won't NICE-on under 20 mph unless I have to.

I do not have a video to help you but if you have a specific question on methods it would be good to type it and I'd bet you get some good advice.

A year or so ago when I started on this site I could not do P&G and restart nice and easy and a few on here told me how it's done and man was that every a big help as a novice!

Now I can pulse and glide with engine off during the glide for 100miles before my knee says stop it or I'm going to make you regret this abuse. With a warm engine and my High speed P&G between 60 and 50 that's good for 15mpg avg FE or more over steady CC 55mph

The only reason I'd even consider coasting at speed with the engine ON, is the car is Automatic and can't start without the starter, or other limitations like LACK of power steering or brakes with eng OFF...

Thank goodness, I selected a Manual transmission Fit with electric powered power steering.

When doing the pulse and glide are you gliding in "N" or in gear, with a manual? I would think in neutral for less resistance. when doing this though are you restarting your engine with the key or shifting into higher gear and dropping the clutch? Or does this waste more fuel to drop clutch to start? I run a aveo with 5spd looking for the best way?

I glide in N. I restart with the key. I think it's less wear on the clutch. - Dale

Be very careful about trying P&G in public. You need to be fully aware of how your vehicle handles with the engine off and how to get it started again as quickly as possible. Do some tests in a deserted parking lot first. Our goal is to help you get better fuel economy but safety must always come first. If it isn't safe for the circumstances, please don't do it.

Your car will not have power steering with the engine off. It won't be harder to steer at typical traveling speeds, but low speeds will require more muscle. You should be prepared for this and know how much effort it will take.

Power brakes will still be available until you run out of braking vacuum. This vacuum is "replenished" by the engine when running so eventually the "reservoir" will "run dry" if you leave the engine off. Vacuum is only used when the pedal is changing position and you'll find that you should have something like 3 or 4 full presses of the brake pedal before you are down to just unassisted brakes (it could be less, though -- test it out!!). It takes significantly more effort to stop a car without assisted brakes and you need to know what this is like so intentionally use up the vacuum so you can experience it. You do NOT want to find out what this is like in traffic and accidentally rear-end someone because you didn't expect it! I have found that with efficient driving I rarely need more than one press of the brakes at any given time anyway but if I'm concerned I might run out I just keep a steady, even pressure on the pedal to avoid using braking vacuum. Once the engine is running you'll (nearly instantly) have assisted braking back so you should practice starting while braking (both bump and by key).

When turning off the car, there is a right way and a wrong way to do it. I'll tell you the right way and why it is the "Right Way." Whatever you do, do NOT turn the key all the way to the off position when moving. This not only engages a steering lock, it kills all of your electronics -- very dangerous. Only ever turn it back one click from ON position (usually labeled ACC for ACCessory). Once the engine is off always always turn it back to the ON position -- you want to have all of your electronics working... including those airbags just waiting to save your life in the unfortunate situation of an accident. Along with that, you want the key out of ON position for as short a period as possible. To accomplish this, shift to neutral first, let the RPM drop down close to idle speed (not far above 1000 or so), key to ACC, then key back to ON. If you do it too quickly the engine will "diesel" back to life. You want to find that point at which it won't do that anymore and get as close to it as you can -- the goal is always to have that key out of ON position the shortest possible length of time.

Now, as to bump starting... that's another topic and one that is best focused on in deserted areas (remember that empty parking lot? Yeah, this practice goes there, too). Do not "dump the clutch." That is hard on the powertrain and is just plain unpleasant. A proper bump start is a two stage process with the goal of stealing just enough kinetic energy from the movement of the vehicle to get the engine to just turn over. More than that and you'll be wasting energy and causing a jarring effect to the powertrain. Less than that will fail to start the engine. Bump starting is easier at higher speeds simply because there is so much more kinetic energy available. Lower speed bump starts are "rougher" and cause more of a jar because the "contact time" is longer. I'll explain below.

You'll need to know two things before starting. First, you need to know the proper gear for the speed you are traveling. Second, you'll need to know the (approximate) RPM the engine runs at that road speed in the selected gear. When bump starting, select at least one gear up from what you would normally select for the given road speed. If you would typically be driving in 3rd, use at least 4th gear for bump starting. In my Elantra I typically use 5th gear for all bump starting down to about 15mph, then I switch to 3rd. At high speeds, just use 5th. When actually performing the bump start, select the gear with the clutch pedal pressed in, then quickly (but smoothly) let the clutch pedal out until the clutch just makes contact... then immediately press the clutch pedal back in. You want the briefest contact you can give that imparts enough of an impulse to the crankshaft to get the engine to spin and "catch." Think of spinning a basketball on your finger and giving it a glancing blow with your hand... just enough to keep it spinning -- no more no less. (If you can't spin a basketball on your finger, no worries -- I'm sure you've seen someone do it before.) If you try and the engine doesn't start, just try again with a little bit longer "contact" time (the pause before you push the clutch pedal back in). If you feel a "thunk" or jar when you do it, try to use less contact time. Getting it right takes practice and familiarity with the particular vehicle. Done properly, a passenger won't be able to tell you bump started at all. I surprised my wife a few times that way -- she saw me key off but later the engine was magically back on. :D

Now the second part (after getting a smooth start) is to "rev match" to the proper gear. If you bump started in a gear other than the one you need to be in for the speed, shift as soon as the clutch pedal is depressed again, get the RPM to the right level for the selected gear and road speed, then let out the clutch pedal and continue driving as normal. For low speeds this can often be done without using the gas pedal much because there is a natural RPM spike on engine fire up. You can rev match using this by timing the clutch engagement properly. At highway speeds you'll have to consciously bring the RPM up to the correct level before letting out the clutch.

When done properly this is a very fast procedure indeed. Around town I can bump start and get into the correct gear faster than most people can shift from one gear to another. It is significantly under 1s in duration. Other than the fast gear shift movement (if I have to get into a gear different than the one I bump with) the passenger can't tell I've done anything unusual. Work on making it smooth and fast and you'll have a very useful tool in your arsenal.

Once again, safety trumps everything else. Do NOT do this in public with anyone around unless you are extremely comfortable with it. I don't find this any more complicated than learning to drive a manual transmission, but just like that you need to have the actions be so familiar that they are second nature. If you have to stop and think about some piece of it, your critical reaction time is extended way into the danger zone. Don't do this unless it feels completely natural and you can just "feel" what comes next.

Now, a couple of other things about this. Different cars require a different "touch" when bump starting. My Elantra can be bump started extraordinarily smoothly. The Insight is a much lighter vehicle and is much more difficult to bump start smoothly. Your Aveo might take a fair degree of finesse to get a smooth bump start. The other thing is that without a gauge to monitor your progress, P&G can very easily really tank your fuel economy. You need that average mpg readout so you can be sure that your average is moving up after every pulse and glide cycle. Without that to see what your results are as you do it, you could be throwing fuel right out the window. Particularly at higher speeds.

The goal is to pulse at somewhere around 75% load (think of it as total output power available at that RPM in the particular gear you've chosen). Without a SG you can approximate it by finding that pedal level that doesn't give you any more power than just a little less pedal (you know... that point at which it doesn't matter if you floor it, the car just isn't going to accelerate any faster). That would be your 100% load level. Back off to about 3/4 that acceleration level and you should be around 75% load. Note that this pedal position will change as RPM varies. At low RPM it will be a very different pedal position than at high RPM. During the pulse, you should ever so slightly adjust your foot position as you accelerate to "chase" that load level. The goal is to get into the efficient power band of the engine for a short period (with the throttle plate more open than steady state cruising -- a mostly closed throttle plate isn't very efficient for the engine), then coast with the engine either running in Neutral or completely off in Neutral. (Note that you shouldn't just coast with the clutch pedal depressed -- you'll wear out the throw-out bearing and labor to replace that isn't cheap). When first learning how to P&G, use the engine running in N at idle for the glide portion. It is one less complication for you to remember initially and much closer to your pre-P&G driving habits. At high speeds there isn't much difference between engine at idle and engine off during the glide phase. At low speeds, it can be the difference between improved mileage and worse mileage than simple steady state driving (engine off coasting is always more efficient -- more so at lower speeds).

Pick two speed set points which when averaged will give you the speed you wish to travel. (Stay legal, here. ;)) If you want to drive at about 45mph, pick set points equal distances above and below that speed. Deltas (differences in speed) are important here as they affect the length of time you are gliding. 10mph is good (so something like 50mph/40mph for our 45mph desired speed example), though a little less can also be (not as) effective. My experience has shown 15mph deltas to be pretty close to ideal in most circumstances for maximizing fuel efficiency (so something like 53mph/38mph). Lower speeds are better as the air resistance is less and allows the glides to last longer.

Try to keep your RPM between roughly 1400 and 2300. I wouldn't go higher than the 2300 but I sometimes go lower than 1400 (but I have a pretty torquey engine in the Elantra). This often means you should pick a lower gear than you might for steady state driving when pulsing. For normal driving you'll want to shift at no higher than 2000 RPM and use a gentle acceleration. That's what I use to get up to speed if I'm not using P&G (rare for me anymore ;)). With a gauge you'll want to watch that average and make sure it goes up after every cycle. The number will go up and down through the cycle but should reach a maximum at the end of the glide phase. That point in every cycle should be at least a little higher than the last cycle.

Finally, as you can imagine this can be very annoying/confusing to following traffic. Keep this in mind. A safe driver is a predictable driver. You can use P&G in traffic (I do all the time), but make sure it doesn't surprise people. Either do it when no one is around, or vary your use with the traffic flow. If there are gaps in the traffic, pulse to your peak speed as traffic reaches you, then glide down as they pass you. You have to vary your speed set points to deal with traffic properly and it isn't an easy skill to learn. As always, stay safe -- if you can't do it with minimal impact to traffic, don't do it. If you can't do it safely, don't do it.

As for wear on the clutch... if you are smooth about it the wear is actually quite a bit less than that caused by starting the car rolling from a complete stop. Several of us have been doing bump starts for many many thousands of miles on the original clutch with no issues at all.

I know that was long winded but hopefully it serves as a good guide for your efforts. This is easier to understand if you see it in action so if you are ever in this area look me up and we can go out in a car for a clinic.

Print that, post it on the wall, read it read it read it, memorize it, tie it on your forehead, etc.

Well done, Sean.

Thanks again sean! I love how willing you guys are to help people out! I would like to get good as well and help others achieve a better target mpg! I will definately be reading that a few times thanks!

Bottom line I need a sg!

Very good guide. I've been using P&G for over a year now, but I think my RPMs are just a little too high. I'll never be able to quickly find out the best P&G, as I don't have a scangauge(1994 corolla), but I may drop a gear on my P&G now and see if there is any improvement.

Thanks Sean!