New "Hypermiler" - trying to save

[carbonx]

Newbie here, been reading the forum for a day now. Very nice tips, may I say.

I've got a 1998 Hyundai Accent with 111.3k miles on it - 4k of my own. It's in perfect condition, barring the engine. It's fine and runs, but it's dirty as hell. I've been trying to run a fuel system cleaner since I got it, that STP stuff. I've noticed a pickup in the car's power, not much as it's only got 94 HP stock, but it's been picking up.

I'm now looking at hypermiling.. but a reduced version. My last tank, driving regularly (full throttle from a stop to 45, using the brakes normally -- driving like a kid ) got me 24.9 MPG, apparently.

I filled up tonight, and I've already started the hypermiling experience. Throwing the car in neutral and coasting, steady foot up hills, don't floor the gas off the line, let it roll and then use some gas.. etc. I haven't, however, had the balls to EOC. I've done two EOC attempts in my neighborhood, and my brakes get hard to pump (usual) and the steering gets hard to turn. I'm afraid that if I do that in traffic, I'll end up causing a wreck.

Basically, I'm looking to turn that 24.9 into 30, or 35 even. I can't EOC or P&G, I can P&GwI (Pulse and Glide while idling), but I'm not ballsy enough to turn my car OFF in traffic.

Is there a way to do get 5 or 10 MPG out of my car? I want to try to SeaFoam my car out to get any residual crap out, but if I don't, can I still achieve that kind of a pickup?

Thanks for any responses, it's much appreciated.

[cfg83]

carbonx -

Welcome to EM! I assume you have a manual. Based on this, I think you can work your way up to 35 MPG :

1998 Hyundai Accent - 5 Speed Manual - Compare Old and New MPG Estimates

New MPG
25 City
33 Hwy
28 Combined

Old MPG
28 City
36 Hwy
32 Combined

What's your typical driving scenario? Short trips or long commutes? Urban or suburban or rural?

CarloSW2

[carbonx]

Thanks for the post, CarloSW2.

I've actually got an automatic transmission - probably the biggest thing I left out of my first post.

I live in a not too big town, so somewhere between Urban and Suburban. I live about 6 miles from work, and my girlfriend live about 10 miles from me. Usually I don't go more than 30 miles at a time, but there are times where I need to.

Most speed limits around here are 55, then drop to a 45. Most back roads have a limit of 35, rarely do I hit a 25 or a 15. From home to work, there are 8 lights.. and from here to my girlfriends, I want to say there's 20.. but I could be off on that by a few.

I'll usually avoid traffic by taking some back roads at peak hours, one cuts through town and is a 35 all the way through, so I can relax and take it at 32 MPH most of the time. I used to be a speed-demon, gotta go type guy... that stopped when I got a hefty ticket late one night. Now it's time to conserve and save my money, it's going in too many places.

The most time I've spent in my car - driving at one time - probably no more than an hour, unless there's an accident and I can't avoid it. I don't go on the highway at all, if that helps any.

[NeilBlanchard]

Hi,

You can get above the new Combined EPA number, with "free" stuff like increased tire pressure and ecodriving techniques. My wife gets ~7.5% above, and that is during the winter, in her automatic Scion xD.

[PaleMelanesian]

As they teach truck drivers, "Aim High". Look far ahead and anticipate any and all conditions. Especially watch traffic lights, and adjust your speed early, so you can roll through on the green. Stops are TERRIBLE for gas mileage.

[carbonx]

Well, I've gotten a tune-up on the car (nothing real major, new plugs and wires [gapped correctly], and a new air filter). I'm still waiting to do an oil change and a rotation.

I look as far ahead as possible while still looking directly in front of me. I anticipate the lights, as they're pretty easy to know around here. Traffic at times can suck, but it's not too bad if you know the area.

I tried EOC'ing today, and once I turned my car back on I had absolutely no first gear and no overdrive, so I was stuck in third at 3k RPMs on the way home. That probably blew my tank, but... As soon as I power-cycled the car (turned it all the way off and all the way on), first and OD came back. I'm not sure if that's a side-effect of the EOC attempt itself, or if the car is just getting too old for that.

Thanks for all the tips so far, I'm enjoying them.

Did have one question, however. When you're going up a hill, is it better to go up it with minimal RPMs, or "attack" it at moderate RPMs? We have a few long hills that you can get away doing between 40 and 45 at around 1.9k RPMs. Would it be better to go slightly above the speed limit and hit them at 50 at 2.4k RPMs just to make it over the hill faster? Probably a stupid question, but might as well ask

[Lazarus]

Welcome to the site enjoy the journey.

Since you have an automatic it is critical that you learn your shift points. Once the car shifts you usually have about 5 mph before it will downshift. The best mileage will be in OD at the lowest possible rpm without down shifting. The transmission control unit will learn your new driving style and the shift will come at lower rpms now that you are not WFO from start.

Learn to read the terrain. Use the slight down hills to your advantage. As far as the hills go. Use a bleed technique. Keep the speed constant until you get to the beginning of the hill and then keep the same throttle position and let the speed bleed until it get just above the point of downshifting and then keep the MPH there so it won't down shift.

To get good at the game takes a while. There really is no silver bullet but by building on each aspect of the drive with technique alone you can get some good numbers. Doing easy mods to the car is icing on the cake. If you're doing 25 MPG now, with the way you describe your style, if you look at the tips and techniques and control the foot you should easily get the 10 MPG you're looking for especially when the weather warms up a bit.

Good luck and if you can afford to get instrumentation it will easily pay for it self.

[comptiger5000]

Hills depend on the car. With an auto, you don't want to attack too hard, as you can't prevent it from unlocking the TC and/or downshifting, so your RPMs will go sky high. With a stick, you can give it some juice to get the engine in an efficient working part of the spectrum (high load) on longer hills. If the hill is short enough, just coast.

The only time to try to maintain, or even gain, speed on a hill with an auto is in a car with a lot of low-end power and a fairly lax tendency to downshift (not your Accent, I used to have a 2000 Elantra 2.0 auto, it was a dog on hills).

[carbonx]

I know the terrain here - been here for 18 years and it's printed in my mind. I love saying "BUMP" and then you feel the bump to my out of town friends.

Small hills have always helped. Sadly, it's been raining the past two days, so my neutral coasting has been limited at best, thanks to the resistance of the rain. It's sunny out now, so I'll get some good coasting in tonight.

The Accent is a dog when it comes to hills. Got a speeding ticket recently - was going up a hill and hit 60 without realizing it.. speed limit was 45.... and blue lights in my rear-view. Oh well, life goes on. I've been getting up to 50 before I hit the hill and then keeping my foot and the RPMs around 2k, and letting it slow to about 43 before I hit the top of the hill (in the slow lane and ridge riding). I'm up to about 70 miles on this tank, and it's at almost 3/4ths of a tank to go. That would, theoretically, put me at 240 miles for the tank, still at 25 MPG. We'll see how far I really get, though.

I've been reading a bit about over-pressurizing the tires. I'm set at 33 PSI right now, my dad's a mechanic and sets it there. Should I go pump them to 35, even 37? I don't really feel good about going much higher than 37.... I'd have to read the maximum PSI on my sidewalls before I do, but would it create enough of a difference to be noticeable?

Sorry if I'm asking too many questions. Just trying to see what I can get out of this old car! Thanks a ton for all your responses!

[PaleMelanesian]

My last set of tires I ran at 40 psi. They're 44-rated, and the car calls for 32. They wore out on the edges, just like they should for UNDERinflated tires. Now that I'm running *much* higher pressure, the wear on the new ones is even across the tread after 30,000 miles.