Hugely dissapointed with hypermiling results
 

Ok, so my car is an 02 saturn sl2 auto. I dive with a permit so my grandmother also drives the car. Although she isn't an ecomodder or a hypermiler she is preety conservative with her driving. We also do only city driving sadly however, after calculating this weeks mileage i got BELOW EPA(25 mpg city) with (125 miles on 5.12 gallons of gas) This yields 24.4 mpg. So far what I've been doing: coasting down hills (engine on in gear), not revving up past 2000 rpm when possible when accelerating, only turning the ac on when other passengers say so ( cuts ac usage by 1/3 ), avoiding excess idling whenever possible, tricking the transmission to go into fourth at 35 (allows me to go 35 at 1500 rpm) and once in a while taking a slow parking lot hill in neutral. Also note I am not allowed to modify the car aerodynamically and for comfort/ apparant safety reason I am not allowed to put the tire pressure above 35 PSI. WHAT DO I DO???!!!

Maybe it's ready for a tune-up.

hmm possibly but we already had it at the mechanics tiwce this month

Does the parking brake release?

I think you are driving right; I think you should perhaps do somewhat better for fe. Any history of the car's fe?

Possibly brakes are sticking. After driving it for a few miles at 45mph or higher, stop and feel the temperature of each wheel at its hub to see if one is hotter than the others. Also could jack up the car and spin the wheels by hand with the brakes off to see if one is sticking.

Could be running rich. If it's only driven in the city, an Italian tune up might not hurt, either, though it sounds like you'd have trouble getting away with that.

Sometimes conservative driving means driving with one foot on the gas and one on the brake. My mom's driving absolutely drives me crazy: accelerate up to speed, oops, one mph past, hit brakes, repeat. I love her, but I was at risk of whiplash even without getting in a wreck.
That said, depending on how much stop and go you are actually seeing (ie, how much time is spent at stoplights), it can destroy any gains you might see by hypermiling.

What's an "Italian tune up"?

Hypermiling takes practice. Each car is different. You need to get a feel for what works, and what doesn't. Bummer about not being able to pump up the tires. Have you considered getting a scanguage?

thx guys didn't think of the brake issue as for the engine running rich how could one just you just check that kind of thing. We spent $900 at the mechanics this month so any easy diy info would be helpful.

as for my grandmother she does drive using one foot and she does act pretty much like a regular driver.

How long are your normal trips? If the distance is short, the engine never warms up.

I have a lot of stop signs / lights in my area but I figured I could still hypermile my car to get better FE

my usual trips are like 5 miles (grocery store is about 6 resturuants are like 3 umm beach is like 5 it varies but there not too long). I would ride a bike to and fro but my family usually hangs with me.

You are doing everything right :thumbup: .

What I would do is lay off the hypermiling for a while untill you go through a full tank of gas. This way you can see what kind of mileage that the car is normally getting.

You already know this but.......
Set the odometer at '00000' when you full up, then take note of the mileage on the odometer when you fill up. Divide the miles traveled by the gallons purchased. A reciept is a good way to keep track of things like this.

125 miles is not really an accurate distance to test with, so try at least 300 .... but don't run that thing empty though !

yes CD thank you I am using reciepts and the odometer however, if I understand you correctly your saying I should go longer on a single tank and that I should stop hypermiling for one tank?

No sry I don't really have any history of the cars fuel economy my grandma didn't keep track before I had it.

What I am saying, is that to provide a comparison figure, you need to first find the 'normal' mileage of that particular car that you drive.
Just because the window sticker says a certain MPG figure, doesn't mean that every Saturn car like yours will get that same mileage. You could have engine problems, or other things wrong that cause your mileage to fluctuate.
By running through a full tank and keeping note of the mileage, you can see what kind of mileage that the car gets without hypermiling, and then compare the results with the ones that you get from a tank using hypermiling.

( So yes, drive longer between fill-ups - the longer the better ( more accurate ) , and skip hypermiling for one or two tanks till you get a good comparision figure )

Good luck ! :)

gotcha

will do if all else fails but first im going to check tire psi and brake sticking and see if can improve more

Someone already mentioned it, but: you would really benefit from instrumentation if you want to fine tune your driving technique.

ScanGauge or MPGuino

sn0w3n -

Yeah, ya gotta have a baseline.

You have a 2002, so you shouldn't have the "plastic ECTS" problem that previous-gen S-Series have before they switch to the brass ECTS (that your 3rd gen S-Series already has).

If you find that your baseline is below EPA, you made need to spend some time here :

Saturn S-Series - SaturnFans Forums

CarloSW2

to metrompg, I would love to get one of those but I don't think you truly comprehend how broke I am. It would come out of my pocket and I make $60-100 a month doing odd jobs.

I don't have fancy instrumentation either.

I think it would help... some... a bit.

sn0w3n -

Ok, an affordable option for you is a vacuum gauge :

http://ecomodder.com/forum/showthrea...uide-3428.html
http://ecomodder.com/forum/showthrea...tall-6303.html
http://ecomodder.com/forum/showthrea...gauge-368.html


CarloSW2

So, you're taking 5 mile trips, with a lot of stop signs along the way. Let's say it takes 2 miles for your car to warm up to operating temperature (I have no idea how long it takes, but lets just use 2 miles), then 40% of your trip each time is with the car still trying to get up to temperature, and not giving you good fuel economy. The EPA's 25MPG city rating is based on an 11 mile trip, so the engine is warmed up for a longer time.

Also, it sounds like you usually have several other people in your car. Extra weight might not make a huge difference, but it certainly doesn't help the FE.

So, considering these things, it sounds like you're doing a great job getting anywhere near EPA. Most people who get way over EPA ratings drive mostly highway, or rural roads where they can safely go slower, and practice 'extreme' hypermiling tactics.

Short-trip city driving kills FE. I'm lucky to be pulling 20 mpg right now because all I've done is short-trip city driving. It's bad when one's commute starts across from downtown and traverses through the city core to a point on the other side. This from a car that I can yank 36 mpg highway out of.

Can you install a block heater? Do you know how to install a vacuum gauge? Do you think you could figure it out?

Being broke isn't a good reason to not do things. Invest more time and thought than money, and you're still going to come out ahead. It just takes longer.

Money tends to be a substitute for thinking and ingenuity... "Why should I think of a way to do this if I can just go buy it?"

Except, that doesn't work when you can't "just go buy it", especially when it's due to lack of funds. You've obviously got internet, so google a few DIY solutions to things.

You could save a LOAD of money by just learning how to fix your own car. Mechanics are rip offs because they can be, and you won't know the difference anyway. Mechanics usually assume that you have no idea what they're talking about when they changed your Kneuter Valve... and thus, they can overcharge you for it, because they're better actors than Mechanics. I think some schools probably teach them to act, so they can get more money with less information. :Rolleyes:

Hi,

Someone already mentioned it, but it is critical to have your tires pumped up -- try 38-44psi if your tires have 44psi as the sidewall max.

Also, your tires can tell you if you have an alignment problem -- are they worn evenly?

If you are sitting at traffic lights, and you can see the lights in the other direction -- shut your car off while you are sitting, and start it when you see the yellow in the other direction (or when you see the brake lights go off a few cars ahead of you). Or, at least put it in neutral while you sit.

The trick with ecodriving is to only accelerate up just enough to let you coast to the next stop -- have you tried coasting in neutral? If you need to slow down, downshift to 3 or 2 and let the engine do what it can to slow you down, and use your brakes only when you have to (at the end right before you stop). Think of it as a challenge to keep your brakes cold!

The difference in fe between 35 and 44 psi ain't a whole lot. If the passengers want 35, let 'em have 35.

If you aren't ever- or are rarely- getting into top gear and/or overdrive then that's one of your biggest problems. On that note, it is possible to accel too slowly and take too long to get in top gear. Accel briskly but then, as you do, let off at the lowest speed where top gear engages and go from there.

I wouldn't downshift to slow down in town. I coast- usually in D- to a degree that makes minimal braking necessary only at the very end. It's a generally true statement, though, to drive as if your brakes are the enemy.

Block heater, grille block (at least partial), and engine blanket would all help on those multiple short, cold trips. If that is all this car ever sees, it might be beneficial to take 'er out on the freeway once in a while and run the snot out it- get it warm for a while. That is the "Italian tune-up".

ok thank you everybody this is a lot of info but a will try to tackle it. Currently I'm letting my grandma drive through the next tank because she behaves like a regular driver. I'll monitor this mpg and keep you posted. Then, I'll look into that block heater buisness as lack of warm up time can be pretty huge. Thing is though keep in mind my parents don't want me to tinker with the car to much so I'll run it by them and see how it goes.

don't know about the states but shell sell v-power over here, I normally put a tank of it in every so often - that and get some injector cleaner additive and get you cars alignment checked , cos if you've kerb'd a wheel you could be scrubbin' down the road

most times we fill up we use v power but for cost reasons we sometimes dont (yes it is in the states)

I can't suggest that you buy a certain fuel, I can't suggest that you use additives...

I believe that both of those things have always been claimed to be good, yet the supporters of either have never provided real evidence that either actually does anything.

Alignment, I can agree with. It takes more energy to slide your foot across the ground than to roll it.

Late to thread, but an "Italian tune up" is when you take the car for a nice drive in the HIGHEST rpms you are comfortable with, usually about a mile or two. This cleans the carbon off of the spark plug electrodes and sometimes dislodges carbon on valves. The term originates from Italian sports cars being taken for a "joyride" by mechanics when brought in for running rough. Usually the cause of the rough running was the owner "babying" the gas pedal, and carbon building up as a result.
I do not recommend this type of action, as the amount of potential for catastrophic engine failure, increased wear and overall safety of the action. Just throw a bottle of fuel injector/carburetor cleaner in the next gas tank. Next, you should take the advice for the rest of the people on this thread.

6 miles? So buy more bikes if you all need to go. You'd probably have room for the groceries :)

I think you're being very optimistic thinking that you can get great mpg driving such short trips. I drive a diesel, gently, out of town, usually about 30 miles, with hypermiling tactics, and don't get that much above manufacturer's figures...

I'm kind of in the same boat as you and I can attest that your weak mileage is probably due to your short-trip driving.

I started Park-n-ride for my commute to work in the monrings. I drive the car 3 miles to avoid a major highway and a major hill into my subdivision, and I bike 3.4 miles into the office.

Since doing this, I'm driving much less, which is great, but I'm also taking a loss in fuel economy. My last tank was down from my average 22 to 19 mpg.
Honestly though, I could care less. The goal here is not just to have great MPG numbers for bragging rights or for some other superficial reason. The goal is to use less fuel. Just because the overall MPG number is lower doesn't really matter. I went almost 2 months without buying gasoline, thanks to my bicycle and with a little help from my scooter.

I didn't put gas in the Kia between 5-15-09 and 7-15-09...
I think that's awesome, given that the average fill-up over the last 2 years occured 2 times per month. I'm hoping to extend this tank even further.

jonathan150cc -

Yeah, that's the right way to look at it. Because I am a commuter, I am a major offender. I used to live 2+ miles from work, so I was the "good guy". Now I live 35+ miles, so I am the "bad guy" (at least in my mind).

CarloSW2

I read through the thread and didn't notice any mention of the O2 sensor.

There are some myths (IMHO) about these sensors and when they go bad.

First of all, they don't always throw a CEL, and secondly, just because they still respond, doesn't mean that the response is fast enough to provide high MPG.

I have replaced the O2 sensor on my Tacoma twice, both times because engine work was done (contamination in the exhaust stream), and neither time did the light come on.

But in both cases, my gas mileage went down by about 25%, something to consider.

Chipsndukes

Wow, that's awesome. Sounds like you'd be a perfect candidate for a Forkenswift. :thumbup:

Those short trips are killing you. My diesel pickup only gets about 12mpg over 6 miles, yet I can get over 28mpg over 55 miles.

My 99 Metro can just get 40 mpg over 6 miles, but can get over 60 mpg over the same 55 miles.

I believe hypermiling techniques can be realized over longer distances, rather than short trips. Don't idle and let it warm up - just get in, seatbelts on, start it and go. Use light throttle to use the least amount of horsepower. A heavy foot at low RPM is very wasteful.

If you have a Phillips 66 gas station around, I believe most all DO NOT use alcohol/oxygenated fuel (check the pump sticker). Use the lowest octane.