tips for better gas mileage with my manual transmission car?

[Zenmervolt]

The engine isn't tiny, it's 1.6L and it's modern. You seem to forget that they've made 1.0-2.0L engines since the 1960s that were put into actual cars and those engines were far less powerful than they are today. It's true cars have gained some weight but they have also gained some power and it's safe to say the power to weight ratios have improved considerably even from 15 years ago, let alone 40 years ago. Shifting early in an Aveo will improve fuel economy. As long as OP can accelerate smoothly without any racket and isn't flooring it (after about 85%+ throttle input, depending on make/model) so the car doesn't enter into Open loop which ignores O2 sensor output, he will be fine.

As for OP driving up hills, he will have to play around with the shift points and see what works for him so that the engine doesn't ping/knock/make horrible noises. I live in the SF Bay area so I'm familiar with hills and so I know what shift points work and don't work on the lower displacement cars. The only time I hit 3K RPM+ is when I'm purposefully wringing out the engine, not just to "drive normally" whether that be a 1.6L engine or a 5.7L engine.

And you seem to forget what driving a car with an engine that small is like. As well as completely ignored the fact that I posted the engine's goddamn power figures (since, you know, if you'd actually looked at those you'd have had to agree with me). The Aveo's engine makes a whole 106 ft-lbs of torque at 3,800 RPM. Short-shifting at 2,000 RPM is just absurdly out of the powerband; you'd be looking at maybe, maybe 50 ft-lbs at 2,000 and about 25 horsepower. Even with the Aveo's 2,400 pound curb weight, that's not enough power to do anything with.

2,000 RPM is, quite simply, too low to shift at for that car to have anything resembling reasonable acceleration given the OP's car and engine.

Bottom line, a 2,000 RPM upshift point for a 2008 Aveo is, well, stupid.

https://www.youtube.com/watch?v=LR3uFfT-qtM

ZV

 

[RLGL]

My 2001 Neon gets 30 summer and 27 winter.

 

[Yuriman]

My 2001 Neon gets 30 summer and 27 winter.

I wonder what it is about the Aveo that prevents it from doing better? I get 25-50% better mileage in a Civic which has 40% more power. The Civic is even geared in a retarded way for economy.

 

[pauldun170]

I wonder what it is about the Aveo that prevents it from doing better? I get 25-50% better mileage in a Civic which has 40% more power. The Civic is even geared in a retarded way for economy.

On the manual, it sounds like they screwed up the gearing. With the auto, sounds like the calibration sucks.
Doing a little reading on it, sounds like the folks with the best luck live in areas with no hills, have a properly broken in engine and have yet to have the o2 sensor go out on them. Saw a few posts where owners with relatively new cars reported the o2 sensors going.

With a manual, shift early and accelerate slowly (aka light throttle). Do your best to never slow down and keep it under 56mph if you want the best fuel economy. No need to over think it.
If by doing that your fuel economy still sucks then either fix your car or get another car or just be happy that your car still runs.

An Aveo getting 25mpg in mixed driving is NOT uncommon. Especially in local, short distance, hilly areas.
Just like the Smart car, small does not automatically mean good fuel economy

 

[tortillasoup]

And you seem to forget what driving a car with an engine that small is like. As well as completely ignored the fact that I posted the engine's goddamn power figures (since, you know, if you'd actually looked at those you'd have had to agree with me). The Aveo's engine makes a whole 106 ft-lbs of torque at 3,800 RPM. Short-shifting at 2,000 RPM is just absurdly out of the powerband; you'd be looking at maybe, maybe 50 ft-lbs at 2,000 and about 25 horsepower. Even with the Aveo's 2,400 pound curb weight, that's not enough power to do anything with.

2,000 RPM is, quite simply, too low to shift at for that car to have anything resembling reasonable acceleration given the OP's car and engine.

Bottom line, a 2,000 RPM upshift point for a 2008 Aveo is, well, stupid.

https://www.youtube.com/watch?v=LR3uFfT-qtM

ZV

If a late 90s geo metro with a 56 PEAK hp motor can make it around the Bay Area, or a CRX HF with a 62hp-72hp motor and a very tall final drive of 3.25:1, I don't see why an Aveo can't do something similar with a much shorter gear ratio'd transmission. I mean sure if OP is climbing a 15% grade @ highway speeds, it's probably reasonable to assume OP will have to down shift a gear or two but I'm thinking of hills @ city speeds. He should be able to make it up most hills below 3K RPM. Again highly dependent on the roads he is talking about.

 

[OverVolt]

I will try to hit the bottom of a hill before ascending with some momentum, keep giving just barely any gas in my automatic to ensure it doesn't downshift, and I lose 5-10mph by the top. Its fine when there isn't any traffic. Driving in rush hour eliminates basically any economical use of fuel.

Engine braking is totally wasting all the potential energy you had stored up at the top of the hill. When I drive on country hilly roads I don't mind letting the hill just take me down up to 60mph or so before I brake if it is safe to do so and then just barely keep on the gas for the next hill and let it go down to 45-50mph by the time I crest the next hill.

Depends on the road and the hills I'm sure.

I've driven on a 1mile 6% grade downhill and you coast 85mph down that, so I did have to brake the last quarter mile or so to be safe. I didn't want to fry my brakes there were like 5 similar uphill/downhill grades in a row on this one particular drive. Run-away truck ramps and everything. It was fun, honestly. The trucks used the jake brake and stayed around 50mph. In an automatic car you don't have many options other than to just coast.

 

[tortillasoup]

You can downshift in an automatic car...

 

[desura]

Thx for replies. To answer a few questions...

1. Have had the car for about a year now. Probably put 5k miles in it. Had like 60k at purchase. Car was a gift from a family member.

2. Main commute is 7-8 miles. 2\3 city and 1/3 highway.

3. Have had brakes changed, oil replaced within last 5k miles. Running 34 psi in tires. They say they can handle 44 psi so I might try 40 psi.

4. Engine light is on. Have considered spark plugs, o2 sensors, or air filter might need changing out.

 

[OverVolt]

You can downshift in an automatic car...

Herp Derp I can drive a manual as well. What I mean is that my automatic doesn't downshift on hills if I'm light on the gas. Food for thought to try depending on the hill and if he can start at the bottom with a bit of speed.

 

[OverVolt]

Thx for replies. To answer a few questions...

1. Have had the car for about a year now. Probably put 5k miles in it. Had like 60k at purchase. Car was a gift from a family member.

2. Main commute is 7-8 miles. 2\3 city and 1/3 highway.

3. Have had brakes changed, oil replaced within last 5k miles. Running 34 psi in tires. They say they can handle 44 psi so I might try 40 psi.

4. Engine light is on. Have considered spark plugs, o2 sensors, or air filter might need changing out.

Short commutes burn far more gas because the engine doesn't hit peak efficiency until warm. Thats the main problem hands down.

 

[Zenmervolt]

If a late 90s geo metro with a 56 PEAK hp motor can make it around the Bay Area, or a CRX HF with a 62hp-72hp motor and a very tall final drive of 3.25:1, I don't see why an Aveo can't do something similar with a much shorter gear ratio'd transmission. I mean sure if OP is climbing a 15% grade @ highway speeds, it's probably reasonable to assume OP will have to down shift a gear or two but I'm thinking of hills @ city speeds. He should be able to make it up most hills below 3K RPM. Again highly dependent on the roads he is talking about.

I guarantee you that a late '90s Geo Metro cannot manage that when you're upshifting at 2,000 RPM. Hell, my Turbo Porsche bogs heavily and protests if I force it to accelerate from below 2,000 RPM.

I'm not saying that the cars can't make it up hills at all (which is what your post seems to imply you believe I'm saying). I'm saying that upshifting at 2,000 RPM in a car with only 106 ft-lbs of torque and a peak at 3,800 RPM is just plain stupid. It's going to leave the car accelerating so slowly as to be impractical. Also, there are no 15% grades on highways. A 6% grade is the maximum allowed on highways with speeds of 60 mph or greater. 7% is allowed in certain exceptions and where the speed is below 60 mph. A 6% grade is quite steep, far moreso than most people realize. It's the sort of grade that you'd see in the Rockies with runaway truck ramps all along the side. Surface streets have higher grades, Lombard Street, for example, is a 16% grade (the hill is a 27% grade, but the street's switchbacks reduce the actual grade of the road itself). Looking at some of the streets in SF with huge gradients (like Filbert's 31% grade), you're not getting up those while upshifting at 2,000 RPM. My sister's V8 Range Rover can't manage that and it's got low-end torque coming out the wazoo.

As for your comments about where automatics shift, the automatic in my Volvo typically holds 1st until 3,500 RPM and 2nd until about 3,000 RPM. If I'm being really slow (e.g. 60-second or greater 0-60 time) it might upshift as low as 2,500 RPM. The only time RPM ever drops below 2,000 when cruising is if I'm on perfectly level ground at about 45 mph, when it will drop into overdrive and put the RPM at about 1,800. However, if I so much as breathe on the gas pedal it immediately unlocks the torque converter and the engine comes up to about 2,300 RPM; if I actually try to accelerate with any vigor at all, it drops down a gear and brings the revs up to around 2,800. And this is with the transmission in "Economy" mode.

There are very few engines that actually like to accelerate from below 2,000 RPM. Hanging out below 2,000 RPM in steady-state cruise is fine, but to suggest that the bulk of your acceleration should be happening below 2,000 RPM in a Chevy Aveo is just, well, stupid.

ZV

 

[Zenmervolt]

Thx for replies. To answer a few questions...

1. Have had the car for about a year now. Probably put 5k miles in it. Had like 60k at purchase. Car was a gift from a family member.

2. Main commute is 7-8 miles. 2\3 city and 1/3 highway.

3. Have had brakes changed, oil replaced within last 5k miles. Running 34 psi in tires. They say they can handle 44 psi so I might try 40 psi.

4. Engine light is on. Have considered spark plugs, o2 sensors, or air filter might need changing out.

Short commutes burn far more gas because the engine doesn't hit peak efficiency until warm. That's the main problem hands down.

I would disagree and say that the main problem is that the check-engine light is on. The "default" strategy for when the engine is getting bad readings from sensors is to run richer to protect itself from damage. OP needs to scan the code, find out what's wrong, and fix the problem.

ZV

 

[thedarkwolf]

Engine light being on isn't great either. And don't just throw parts at it to try and fix it. You need to get the codes read at the very least.

 

[pauldun170]

Thx for replies. To answer a few questions...

1. Have had the car for about a year now. Probably put 5k miles in it. Had like 60k at purchase. Car was a gift from a family member.

2. Main commute is 7-8 miles. 2\3 city and 1/3 highway.

3. Have had brakes changed, oil replaced within last 5k miles. Running 34 psi in tires. They say they can handle 44 psi so I might try 40 psi.

4. Engine light is on. Have considered spark plugs, o2 sensors, or air filter might need changing out.

Why would you come on to a forum complaining about MPG when you are driving around with a check engine light?

Get you car diagnosed professionally or find someone who knows how to read the codes of the diagnostic port using a scanner.

 

[Murloc]

apart for the rpm stuff, look into eco-driving techniques.
I had to do a learning day about that (it's compulsory here to get a license) and while it feels like you're driving boring, you're just accelerating and decelerating less, not taking more time.
Here are my statistics: -16% consumption, -8% drive time, +9% average speed, -66% time spent still, +50% shifts.
Maybe they're biased because traffic could have been different in the morning and afternoon but it wasn't noticeable.

Of course it takes an effort to keep doing all you have to do so I went back to driving the usual way.

 

[kitatech]

Why would you come on to a forum complaining about MPG when you are driving around with a check engine light?

Someone on another forum wrote this:
"I like the tires a lot, but we caught a nail in the passenger side front tire. The tire leaks air slowly. Takes about 3 or 4 weeks to drop from around 33 lbs down to about 26 lbs where the TPMS indicates a low tire pressure."

Someone's riding around for WEEKS with a nail in a tire knowing it's leaking...

 

[Yuriman]

Why would you come on to a forum complaining about MPG when you are driving around with a check engine light?

Get you car diagnosed professionally or find someone who knows how to read the codes of the diagnostic port using a scanner.

OP can get an ELM327 bluetooth adapter on eBay for about $9 that will read the codes, all he needs is a smartphone/tablet/laptop and some free software. That dongle can also give things such as engine temperature, instantaneous MPG, AFR, etc., though it's not as convenient as something like an Ultragauge because it ties up a phone or tablet.

EDIT: Most autoparts stores will also do this for free.

 

[tortillasoup]

Herp Derp I can drive a manual as well. What I mean is that my automatic doesn't downshift on hills if I'm light on the gas. Food for thought to try depending on the hill and if he can start at the bottom with a bit of speed.

You mentioned about riding the brakes driving DOWN hill, so you downshift for engine braking.

I guarantee you that a late '90s Geo Metro cannot manage that when you're upshifting at 2,000 RPM. Hell, my Turbo Porsche bogs heavily and protests if I force it to accelerate from below 2,000 RPM.

That depends on the valve timing/lift. It's possible your porsche has no power below a certain band, but what I think is more likely is that you're asking too much from it at a low RPM in that you expect a certain amount of acceleration and the car won't give it to you. I.e. You expect to accelerate at the same rate when you shift @ 3000rpm as you do when you shifted @ 2000rpm.

I'm not saying that the cars can't make it up hills at all (which is what your post seems to imply you believe I'm saying). I'm saying that upshifting at 2,000 RPM in a car with only 106 ft-lbs of torque and a peak at 3,800 RPM is just plain stupid. It's going to leave the car accelerating so slowly as to be impractical. Also, there are no 15% grades on highways. A 6% grade is the maximum allowed on highways with speeds of 60 mph or greater. 7% is allowed in certain exceptions and where the speed is below 60 mph. A 6% grade is quite steep, far moreso than most people realize. It's the sort of grade that you'd see in the Rockies with runaway truck ramps all along the side. Surface streets have higher grades, Lombard Street, for example, is a 16% grade (the hill is a 27% grade, but the street's switchbacks reduce the actual grade of the road itself). Looking at some of the streets in SF with huge gradients (like Filbert's 31% grade), you're not getting up those while upshifting at 2,000 RPM. My sister's V8 Range Rover can't manage that and it's got low-end torque coming out the wazoo.

The Range Rover is also a hell of a lot heavier than a Aveo. The Aveo is actually really comparable to a '96-'00 Honda Civic in terms of weight and power but not fuel economy.

As for your comments about where automatics shift, the automatic in my Volvo typically holds 1st until 3,500 RPM and 2nd until about 3,000 RPM. If I'm being really slow (e.g. 60-second or greater 0-60 time) it might upshift as low as 2,500 RPM. The only time RPM ever drops below 2,000 when cruising is if I'm on perfectly level ground at about 45 mph, when it will drop into overdrive and put the RPM at about 1,800. However, if I so much as breathe on the gas pedal it immediately unlocks the torque converter and the engine comes up to about 2,300 RPM; if I actually try to accelerate with any vigor at all, it drops down a gear and brings the revs up to around 2,800. And this is with the transmission in "Economy" mode.

There are very few engines that actually like to accelerate from below 2,000 RPM. Hanging out below 2,000 RPM in steady-state cruise is fine, but to suggest that the bulk of your acceleration should be happening below 2,000 RPM in a Chevy Aveo is just, well, stupid.

ZV

If you can't manage to get an automatic transmission car to accelerate and shift before 2000 rpm, then you've obviously got a lead foot! I've driven lots of vehicles and I can get them all to upshift @ 2000 rpm while accelerating. You and I obviously have different expectations in terms of acceleration speed. Also have to remember that if the automatic transmission car is used to shifting @ 3000 rpm and you start trying to shift @ 2000rpm, it's going to take some time for it to re-learn its shift habits so in the interim, it will feel extremely touchy. Basically when it gets to 2000 RPM and you know you've exceeded the minimum speed necessary for an upshift, ease off the throttle momentarily so it can shift then you can ease back onto the throttle again until the next shift point.

 

[pauldun170]

Someone on another forum wrote this:
"I like the tires a lot, but we caught a nail in the passenger side front tire. The tire leaks air slowly. Takes about 3 or 4 weeks to drop from around 33 lbs down to about 26 lbs where the TPMS indicates a low tire pressure."

Someone's riding around for WEEKS with a nail in a tire knowing it's leaking...

Geez
Last time I had a nail puncture repaired, it took 10 minutes at a local shop. Didn't even have a chance to finish reading the article I started in the "wait area"
Only reason why I had them do it was because I was to lazy to do it myself.

 

[pauldun170]

OP can get an ELM327 bluetooth adapter on eBay for about $9 that will read the codes, all he needs is a smartphone/tablet/laptop and some free software. That dongle can also give things such as engine temperature, instantaneous MPG, AFR, etc., though it's not as convenient as something like an Ultragauge because it ties up a phone or tablet.

EDIT: Most autoparts stores will also do this for free.

I have a cheapo scanner. Occasionally, I'll get a friend who needs a code reset because they want to sneak it past NYS inspection.
One of these days I'll step up and get a fancy smansie bluetooth scanner.
that or friends who take care of their damn cars

 

[pauldun170]

For poops and giggles I just drove around my hilly neighborhood shifting at 1700rpm.
My Camry 2.4 is a sumo torque monster (lol). Made it up a hill that the local runners don't even try to run in 3rd gear.
I'm going to drive like this for the next tank full or until I get bored or until I have to travel on the highway...whatever comes first.

 

[Zenmervolt]

That depends on the valve timing/lift. It's possible your porsche has no power below a certain band, but what I think is more likely is that you're asking too much from it at a low RPM in that you expect a certain amount of acceleration and the car won't give it to you. I.e. You expect to accelerate at the same rate when you shift @ 3000rpm as you do when you shifted @ 2000rpm.

Yes. It's all the expectation of acceleration. It's not at all related to the way the car shakes and the engine groans when I try it.

And the Porsche makes peak power at a lower RPM than the Aveo does...

The Range Rover is also a hell of a lot heavier than a Aveo.

It also has a hell of a lot more torque. Double the weight, but three times the peak torque and more than five times the torque at 1,500 RPM.

If you can't manage to get an automatic transmission car to accelerate and shift before 2000 rpm, then you've obviously got a lead foot! I've driven lots of vehicles and I can get them all to upshift @ 2000 rpm while accelerating. You and I obviously have different expectations in terms of acceleration speed. Also have to remember that if the automatic transmission car is used to shifting @ 3000 rpm and you start trying to shift @ 2000rpm, it's going to take some time for it to re-learn its shift habits so in the interim, it will feel extremely touchy. Basically when it gets to 2000 RPM and you know you've exceeded the minimum speed necessary for an upshift, ease off the throttle momentarily so it can shift then you can ease back onto the throttle again until the next shift point.

So much bullshit. The AW50-42LE in my Volvo does not learn the driver's habits. It has fixed shift maps. There is no "relearning" period. It doesn't upshift at 2,000 RPM because it's not designed to do so and the engine doesn't work well below that range. You can claim lead foot all you like, but even when I'm behind a loaded semi (frequent since I live in the boonies near quarries) and accelerating very slowly and gently (so as not to run into said fully loaded semi) it doesn't upshift at 2,000 RPM.

As with most car threads, your "advice" is improper. Please, leave these threads to people who know what they're talking about.

ZV

 

[tortillasoup]

Yes. It's all the expectation of acceleration. It's not at all related to the way the car shakes and the engine groans when I try it.

And the Porsche makes peak power at a lower RPM than the Aveo does...

Well like I said, if the engine is making awful noises and shakes badly like something is wrong, then you're probably loading it down too much. I hate to say this but it isn't necessarily an apples to apples comparison as every engine design is different but I think it's safe to say this Aveo can probably handle low RPM shifting. It's true I've driven some cars that just couldn't handle low RPM shifting but those were typically older model vehicles that had less sophisticated computers, etc. You shouldn't make absolute statements like "you absolutely cannot shift before 3K RPM" just because your POS porsche can't...

So much bullshit. The AW50-42LE in my Volvo does not learn the driver's habits. It has fixed shift maps. There is no "relearning" period. It doesn't upshift at 2,000 RPM because it's not designed to do so and the engine doesn't work well below that range. You can claim lead foot all you like, but even when I'm behind a loaded semi (frequent since I live in the boonies near quarries) and accelerating very slowly and gently (so as not to run into said fully loaded semi) it doesn't upshift at 2,000 RPM.

You might want to take a read on this thread about your crappy volvo.
http://www.matthewsvolvosite.com/forums/viewtopic.php?t=62742&p=323058

My sister in law owns a Volvo S60 which is a 5-speed transmission and it will happily shift even as low as 1500 rpm while the transmission you mentioned is a 4-speed. So not only could your transmission have a problem with not being able to shift early (the thread I linked to mentions 3K rpm shifting problem) but you may not be aware of the shift points.

I have to ask, do you actually own any vehicles with some form of variable valve timing? Or are all of your vehicles 15 year old+ euro trash vehicles?

 

[Yuriman]

Thx for replies. To answer a few questions...

1. Have had the car for about a year now. Probably put 5k miles in it. Had like 60k at purchase. Car was a gift from a family member.

2. Main commute is 7-8 miles. 2\3 city and 1/3 highway.

3. Have had brakes changed, oil replaced within last 5k miles. Running 34 psi in tires. They say they can handle 44 psi so I might try 40 psi.

4. Engine light is on. Have considered spark plugs, o2 sensors, or air filter might need changing out.

As others have said, short commute hurts. You could try a block heater in winter if you live somewhere cold, they generally more than pay for themselves. Not really a whole lot else you can do about this. 8 miles is a fair distance to bike.

Dirty fuel and air filters don't actually hurt mileage on modern fuel injected vehicles, you just lose power.

Get that CEL taken care of immediately.

 

[desura]

Check engine light is gone. It seems like it disappeared with warmer weather.

So the aveo does not have a fuel shutoff during engine braking. Well i'll be.

Lots of people don't recommend coasting in neutral but I don't see the problem. For the most part you coast in neutral while going downhill, during which you do not need extra power, just extra braking.

I wish I could bike commute, but the hills make that unlikely. And the highway section too.