How to improve fuel economy in my Camry?

[johnnq1]

I'm always trying to save a penny here and there. When doing daily driving I try to keep the lightest touch on the throttle until I reach around third gear (automatic). Then I give a little more throttle to keep up with traffic...but is there a better way to save gas?

Is opening the throttle at a lower rpm to accelerate from a stop better than opening it more in lets say third gear at a higher rpm?

 

[chin311]

uhm make sure your tires have good pressure, and remove any excess weight you might have in the car, make sure your air filter is in good shape.
only things that really come to mind for me.

 

[dug777]

An LPG conversion would help you massively, but I don't know that you folks have the infrastructure, availability, or the handy excise cut for LPG that would make such a change attractive?

 

[thomsbrain]

http://www.hypermiling.com/

 

[fleabag]

gassavers.org, ecomodder.com

uh, you could try driving below the speed limit when on the highway, look for when your car's torque converter locks up, try inflating your tires to the side wall rating instead of door rating.

 

[Synomenon]

The one hypermiling technique that's saved me the most gas is coasting. I'd try that first. No sense in accelerating towards a red light or stop sign when you're going to have to stop anyway.

 

[geokilla]

It's actually better to get up to speed quickly because you waste more gas accelerating than coasting or cruising. HOWEVER, don't race from red light to red light.

 

[fleabag]

Originally posted by: geokilla
It's actually better to get up to speed quickly because you waste more gas accelerating than coasting or cruising. HOWEVER, don't race from red light to red light.

If you can accelerate while keeping your RPMS low, then I'd agree, but if you're going to be hitting 2,3/4k rpms to get to that speed, then no I'd have to disagree with you.

 

[alpineranger]

Keeping the throttle mostly closed when you want to accelerate up to speed is a really inefficient way of using the engine. However, fully throttle tells the engine computer to operate the engine inefficiently as well. Use a firm and smooth application of throttle when accelerating, and then before the revs get too high, feather the throttle to get the transmission to upshift. Keep the gear selector in D all the time, as the lower gear selectors make the transmission wait later to change into the next gear. Additionally, on all but a few of the newer cars, the automatic does not go into torque converter lock up (the most efficient mode) until you are in top gear and going a certain speed (37mph for my car). So I try to get up to that speed as quickly as possible, feather the transmission to lock up, and then apply more throttle for moderate acceleration up to my target speed, as too much acceleration will cause the transmission to release the converter lock up.

You have doubtless hear the standard lines: inflate your tires, anticipate lights and stops in traffic to avoid unnecessary brake application, remove unnecessary weight, make sure your car is tuned up. I've also found that cruise control is really effective. If you watch what the cruise control does, it often applies the throttle quite vigorously instead of gently, as it has been programmed for very good fuel economy. Watch what it does and try to imitate it.

 

[SparkyJJO]

Originally posted by: fleabag
gassavers.org, ecomodder.com

uh, you could try driving below the speed limit when on the highway, look for when your car's torque converter locks up, try inflating your tires to the side wall rating instead of door rating.

Just don't go below 55 on a road that is 55. That's the approximate average for the best mpg for many vehicles.

Drives me nuts when I see people going freakin' 40 because "they are saving gas." Bullcrap, they're in a lower gear so no they aren't saving anything, they're using more.

 

[CurseTheSky]

Originally posted by: alpineranger
Keeping the throttle mostly closed when you want to accelerate up to speed is a really inefficient way of using the engine. However, fully throttle tells the engine computer to operate the engine inefficiently as well. Use a firm and smooth application of throttle when accelerating, and then before the revs get too high, feather the throttle to get the transmission to upshift.

This. I don't have any scientific or mathematical proof, but I've noticed better fuel economy when I take off at a decent rate (usually letting the transmission shift around 2.5-3k with a 6.5k redline, V6, and 6 speed auto) and feather it when I want a shift than when I feather it the entire time.

I get 24.1 MPG combined in my 2008 Fusion doing roughly 60 to 70% city driving. It doesn't sound like much, but I'm plenty happy with it. Doing mostly highway, I easily get 28-29 MPG as long as I stay off the accelerator.

 

[BassBomb]

If you have the same Camry engine (3.5L with the 6 speed transmission) then you are doing worse by accelerating really slowly... I've noticed this in my dads ES350 which has that engine + transmission

Instead go like 2/3 throttle and get to cruising speed and stick at cruising speed really well. If you see a light turn red coming up, let off on the throttle and coast in early to the light

 

[Zenmervolt]

Originally posted by: fleabag

Originally posted by: geokilla
It's actually better to get up to speed quickly because you waste more gas accelerating than coasting or cruising. HOWEVER, don't race from red light to red light.

If you can accelerate while keeping your RPMS low, then I'd agree, but if you're going to be hitting 2,3/4k rpms to get to that speed, then no I'd have to disagree with you.

While the most efficient way to accelerate is with 75% - 90% throttle opening and short-shifting at 2,000 to 3,000 RPM, it has been shown in instrumented testing that accelerating at 75% - 90% throttle and not shifting until 4,000 to 5,000 RPM is just as efficient as using a light touch on the accelerator.

ZV

 

[Zenmervolt]

Originally posted by: SparkyJJO

Originally posted by: fleabag
gassavers.org, ecomodder.com

uh, you could try driving below the speed limit when on the highway, look for when your car's torque converter locks up, try inflating your tires to the side wall rating instead of door rating.

Just don't go below 55 on a road that is 55. That's the approximate average for the best mpg for many vehicles.

Drives me nuts when I see people going freakin' 40 because "they are saving gas." Bullcrap, they're in a lower gear so no they aren't saving anything, they're using more.

You're wrong. Most cars get their best mileage between 35 mph and 45 mph. I can get high 35+ mpg in my S70 at ~40 mph but I get only ~29 mpg at 55 mph.

Some new cars with 6-speed transmissions may have their ideal mileage at a slightly higher speed, but by and large most cars get their best mileage well under 55 mph.

ZV

 

[Uhtrinity]

Originally posted by: thomsbrain
http://www.hypermiling.com/

Driver attitude will net the #1 improvement. I purposely give my self more time to get where I am going. Most hypermilers have also noticed that if you drive in congested areas you get frustrated and as a result mpgs also drop. For this reason I try to avoid congestion and take alternative routes. Very rarely will I even take the interstate. As a result I have found driving to be more relaxing, more scenic, and will I probably live longer as I'm rarely stressed.

 

[Uhtrinity]

Originally posted by: fleabag

Originally posted by: geokilla
It's actually better to get up to speed quickly because you waste more gas accelerating than coasting or cruising. HOWEVER, don't race from red light to red light.

If you can accelerate while keeping your RPMS low, then I'd agree, but if you're going to be hitting 2,3/4k rpms to get to that speed, then no I'd have to disagree with you.

Good point, I do this in my Insight, but with the condition that rpms don't exceed 2k.

 

[Uhtrinity]

Originally posted by: Zenmervolt

Originally posted by: fleabag

Originally posted by: geokilla
It's actually better to get up to speed quickly because you waste more gas accelerating than coasting or cruising. HOWEVER, don't race from red light to red light.

If you can accelerate while keeping your RPMS low, then I'd agree, but if you're going to be hitting 2,3/4k rpms to get to that speed, then no I'd have to disagree with you.

While the most efficient way to accelerate is with 75% - 90% throttle opening and short-shifting at 2,000 to 3,000 RPM, it has been shown in instrumented testing that accelerating at 75% - 90% throttle and not shifting until 4,000 to 5,000 RPM is just as efficient as using a light touch on the accelerator.

ZV

That will vary based on the car and engine. Even the difference between 2,000 and 3,000 shift points loses me 10 - 15 mpg over a short stop and go trip. I know as it took a lot of trial and error to find the sweet spot.

 

[ebaycj]

All you people suck. Accelerate, dammit !!!!

 

[fleabag]

Originally posted by: SparkyJJO

Originally posted by: fleabag
gassavers.org, ecomodder.com

uh, you could try driving below the speed limit when on the highway, look for when your car's torque converter locks up, try inflating your tires to the side wall rating instead of door rating.

Just don't go below 55 on a road that is 55. That's the approximate average for the best mpg for many vehicles.

Drives me nuts when I see people going freakin' 40 because "they are saving gas." Bullcrap, they're in a lower gear so no they aren't saving anything, they're using more.

That's not true either! Unfortunately in order to counter your argument, I need to make another generalization which hopefully is more accurate than "55mph is approx average for the best MPG". Generally, the best MPG is attained at the speed in which the car attains the highest gear and has the torque converter locked up.

For the Volvo S60, that means around 50mph, where the torque converter locks up and is in the highest gear. However, through some funny programming, if you get up to the point where the torque converter locks up (50mph), set cruise control to 50mph, then lower the speed to like 47 or maybe 46mph via the cruise control, you'll be able to cruise with the torque converter locked up and in the highest gear, yielding the best MPG. This works best on roads where you're ascending (there is a load on the engine). This is true for this specific vehicle because it just so happens that at around 50mph, the car is at around 1500rpm which turns out to be its peak torque. (Peak torque is around 1500rpm b/c it has two turbos and one of them is there to reduce turbo lag)

However, one of my trucks, the torque converter and 5th gear lockup can occur at 35mph and since the wind resistance is significantly less at 35mph than at 55mph, 35mph in this vehicle is much more desirable. The important thing is to try to keep the vehicle in the tallest gear the longest. While I do like to drive at 55mph on the freeway in my truck, one thing it doesn't have is enough low end torque so in order to stay in gear while ascending certain inclines, I must get up to around 70mph before the ascent which raises my RPM higher into its powerband and while that may seem bad, it's far worse to be going 55mph and be at a higher RPM than be going 70mph and being at a lower RPM.

 

[canadageek]

sell it and buy a manual Geo Metro.

 

[johnnq1]

how do you know when the torque converter is "locked up"?

 

[fleabag]

Originally posted by: johnnq1
how do you know when the torque converter is "locked up"?

Aside from feeling it, you've got to watch the tachometer. For example if I'm in 3rd gear in the S60 going 15mph, if I hit the gas, the RPM will rise rapidly and is dependent on how hard I'm pushing on the accelerator and adjustment of the accelerator can vary the RPM wildly while at 25mph in 3rd gear, the torque converter on this car locks up and so when you hit the accelerator, the RPM rises steadily and falls steadily and is entirely dependent on the speed you're going. The best way to test this is to be on a road with an incline, and having slow but steadily acceleration, watching how and when the transmission engages.

Some cars won't have the ability to engage the torque converter until gears 4-5 (on a 5 speed), and on a 4 Speed Automatic Lexus, I think the torque converter can only lockup up in 4th gear and can't lockup in any other gear.

A simple way to know if your torque converter is locked up is this: If your cruising at 1500rpm and you floor it, and the RPM jumps from 1500 to 3500rpm after doing this, your torque converter is NOT locked up. - Your torque converter is locked up when you can see a direct correlation between your speed and the RPM, if your RPM and MPH rise steadily and fall steadily, your torque converter is likely to be locked up (assuming you're not in 1st gear which can make it difficult to discern otherwise).

 

[hans030390]

Originally posted by: IsLNdbOi
The one hypermiling technique that's saved me the most gas is coasting. I'd try that first. No sense in accelerating towards a red light or stop sign when you're going to have to stop anyway.

Next to having a "light" foot while driving, coasting is the best way to save gas. This is especially true with manuals, as you can just put them into neutral when needed.

To extend coasting further, there's the "pulse and glide" method of driving. That also helped.

My '95 Civic can do well over 35mpg in the city like this. Maybe even more now that I've used some fuel cleaners (which did boost my MPG).

 

[Uhtrinity]

Originally posted by: fleabag

Originally posted by: SparkyJJO

Originally posted by: fleabag
gassavers.org, ecomodder.com

uh, you could try driving below the speed limit when on the highway, look for when your car's torque converter locks up, try inflating your tires to the side wall rating instead of door rating.

Just don't go below 55 on a road that is 55. That's the approximate average for the best mpg for many vehicles.

Drives me nuts when I see people going freakin' 40 because "they are saving gas." Bullcrap, they're in a lower gear so no they aren't saving anything, they're using more.

That's not true either! Unfortunately in order to counter your argument, I need to make another generalization which hopefully is more accurate than "55mph is approx average for the best MPG". Generally, the best MPG is attained at the speed in which the car attains the highest gear and has the torque converter locked up.

For the Volvo S60, that means around 50mph, where the torque converter locks up and is in the highest gear. However, through some funny programming, if you get up to the point where the torque converter locks up (50mph), set cruise control to 50mph, then lower the speed to like 47 or maybe 46mph via the cruise control, you'll be able to cruise with the torque converter locked up and in the highest gear, yielding the best MPG. This works best on roads where you're ascending (there is a load on the engine). This is true for this specific vehicle because it just so happens that at around 50mph, the car is at around 1500rpm which turns out to be its peak torque. (Peak torque is around 1500rpm b/c it has two turbos and one of them is there to reduce turbo lag)

However, one of my trucks, the torque converter and 5th gear lockup can occur at 35mph and since the wind resistance is significantly less at 35mph than at 55mph, 35mph in this vehicle is much more desirable. The important thing is to try to keep the vehicle in the tallest gear the longest. While I do like to drive at 55mph on the freeway in my truck, one thing it doesn't have is enough low end torque so in order to stay in gear while ascending certain inclines, I must get up to around 70mph before the ascent which raises my RPM higher into its powerband and while that may seem bad, it's far worse to be going 55mph and be at a higher RPM than be going 70mph and being at a lower RPM.

And even that varies by car .... I'll use mine as an example.

Due to lower available power my cars sweet spot is between 35 - 40 in 4th gear. I can do 100 mpg plus all day long without using electric. 5th gear lugs too much at that speed. At higher speeds 5th becomes the sweet spot, but due to low engine torque mpgs take a hit even on the slightest incline making 4th and 5th a tossup.

Also, not all cars have cvts or automatics, mine has a 5 speed manual.

 

[Uhtrinity]

Originally posted by: hans030390

Originally posted by: IsLNdbOi
The one hypermiling technique that's saved me the most gas is coasting. I'd try that first. No sense in accelerating towards a red light or stop sign when you're going to have to stop anyway.

Next to having a "light" foot while driving, coasting is the best way to save gas. This is especially true with manuals, as you can just put them into neutral when needed.

To extend coasting further, there's the "pulse and glide" method of driving. That also helped.

My '95 Civic can do well over 35mpg in the city like this. Maybe even more now that I've used some fuel cleaners (which did boost my MPG).

And to clarify you don't take the car out of gear, you coast allowing fuel cut which most modern cars can do. If you go to neatral the engine will idle and use fuel. When I decide to go pure ev (as pure as my car can go) the ice goes into fuel cut. On a recent test it did almost 6 miles and resulted in less than .1 lires / 100km, the mpg meter was pegged at 150 mpg. The l/100km number translated to something like 4200mpg or essentially no fuel used other than the initial start.