My car is getting 23MPG average with city and highway driving

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Baked

Lifer
Dec 28, 2004
36,052
17
81
Originally posted by: Eli
Originally posted by: BigToque
I just checked again after refueling my car...

In the city I'm getting 28 mpg.
On the highway, I'm getting 25 mpg.

I think it's a little strange that I'm getting worse milage on the highway than in the city.
That is very strange.

What methods are you using to check your MPG?

I wanna know too. I never bother calculating MPG for my cars, I just log how many miles per refill.
 

jagec

Lifer
Apr 30, 2004
24,442
6
81
Originally posted by: fuzzybabybunny
Generally, but not always. You probably know this already, but driving at 30mph in 5th gear isn't exactly going to use less gas than 30mph in 3rd gear.

Actually, yes it will, at least in the cars I've driven.

The lower freeway mileage makes me suspect the OP isn't using overdrive.

As for using cruise...how does that save gas? Unless a person's constantly accelerating and braking when they're not using cruise, in which case they need to learn2drive;)
 

fuzzybabybunny

Moderator<br>Digital & Video Cameras
Moderator
Jan 2, 2006
10,455
35
91
Originally posted by: jagec
Originally posted by: fuzzybabybunny
Generally, but not always. You probably know this already, but driving at 30mph in 5th gear isn't exactly going to use less gas than 30mph in 3rd gear.

Actually, yes it will, at least in the cars I've driven.

The lower freeway mileage makes me suspect the OP isn't using overdrive.

As for using cruise...how does that save gas? Unless a person's constantly accelerating and braking when they're not using cruise, in which case they need to learn2drive;)

Yeah, I suppose it does depend on the car. In my car driving at 30mph in 5th gear is putting too much load on the engine to keep the car moving at that speed, thus using more gas. It's more efficient for my car to go 30mph in 3rd gear at 2000 RPM than 30mph in 5th at, erm, 1000-1500 RPM or thereabouts.
 

Eli

Super Moderator | Elite Member
Oct 9, 1999
50,419
8
81
Originally posted by: jagec
Originally posted by: fuzzybabybunny
Generally, but not always. You probably know this already, but driving at 30mph in 5th gear isn't exactly going to use less gas than 30mph in 3rd gear.

Actually, yes it will, at least in the cars I've driven.

The lower freeway mileage makes me suspect the OP isn't using overdrive.

As for using cruise...how does that save gas? Unless a person's constantly accelerating and braking when they're not using cruise, in which case they need to learn2drive;)
You get the best MPG when the accelerator isn't being moved around.

When you let off the accelerator and then press it again, you use much more gas during that time period than if you had just been steady(or using cruise).
 

BeauJangles

Lifer
Aug 26, 2001
13,941
1
0
Originally posted by: iversonyin
Originally posted by: DrPizza
Originally posted by: mayonnaise
Originally posted by: fLum0x
dont floor it every time you go somewhere, dont hold down the gas when you see a red light up ahead...just coast, put the windows down. all three of those should help you. The first one is more or less driving casually and with a cruise as much as you can.


Do NOT put the windows down. It kills your aerodynamics and the airflow etc etc. It was proven on The Mythbusters. Windows up = better MPG.

Sorry, but very little is "proven" on mythbusters. It's a show for entertainment. Also, at lower speeds, air resistance is all but negligible. (Make a giant cardboard car, run down the street with it. A little air resistance. Now, push the car. See how much harder it is to push the car.) Compare the air resistance to the resistance of pushing the car.


I think some government agency did a test to this. At higher speed, wind drag does make a difference in car mileage. But I think for smaller car, A/C uses more gas than the lose of mileage cause by wind drag

It depends entirely on your speed and the size of your engine.

At slower speeds it is more efficient to roll down the windows. On the highway it is more efficient to use the AC.

The crossover point is different in every vehicle, but, basically, the more powerful an engine you have the sooner you can start using the AC.
 

BigToque

Lifer
Oct 10, 1999
11,700
0
76
Originally posted by: Baked
Originally posted by: Eli
Originally posted by: BigToque
I just checked again after refueling my car...

In the city I'm getting 28 mpg.
On the highway, I'm getting 25 mpg.

I think it's a little strange that I'm getting worse milage on the highway than in the city.
That is very strange.

What methods are you using to check your MPG?

I wanna know too. I never bother calculating MPG for my cars, I just log how many miles per refill.

I know that from the full marker to my empty marker is 36 litres (the tank holds 46 litres) and then I just reset the trip counter on my odometer after a fill-up. It's just a rough estimate though.
 

fuzzybabybunny

Moderator<br>Digital & Video Cameras
Moderator
Jan 2, 2006
10,455
35
91
Originally posted by: BigToque
Originally posted by: Baked
Originally posted by: Eli
Originally posted by: BigToque
I just checked again after refueling my car...

In the city I'm getting 28 mpg.
On the highway, I'm getting 25 mpg.

I think it's a little strange that I'm getting worse milage on the highway than in the city.
That is very strange.

What methods are you using to check your MPG?

I wanna know too. I never bother calculating MPG for my cars, I just log how many miles per refill.

I know that from the full marker to my empty marker is 36 litres (the tank holds 46 litres) and then I just reset the trip counter on my odometer after a fill-up. It's just a rough estimate though.

What I do it just fill up my tank, set the trip ODO to zero, drive until I need another fillup, then fill up my tank, jot down how many gallons it took to fill and then divide my trip ODO by the gallons that I just put into the tank.

Reset the trip ODO to zero and repeat.
 

Eli

Super Moderator | Elite Member
Oct 9, 1999
50,419
8
81
Originally posted by: fuzzybabybunny
Originally posted by: BigToque
Originally posted by: Baked
Originally posted by: Eli
Originally posted by: BigToque
I just checked again after refueling my car...

In the city I'm getting 28 mpg.
On the highway, I'm getting 25 mpg.

I think it's a little strange that I'm getting worse milage on the highway than in the city.
That is very strange.

What methods are you using to check your MPG?

I wanna know too. I never bother calculating MPG for my cars, I just log how many miles per refill.

I know that from the full marker to my empty marker is 36 litres (the tank holds 46 litres) and then I just reset the trip counter on my odometer after a fill-up. It's just a rough estimate though.

What I do it just fill up my tank, set the trip ODO to zero, drive until I need another fillup, then fill up my tank, jot down how many gallons it took to fill and then divide my trip ODO by the gallons that I just put into the tank.

Reset the trip ODO to zero and repeat.
This is exactly what I do and is the most accurate method AFAIK.

I don't know really how I would calculate city and highway driving.. using this method is an average over the tank.

For me, this is something like 75-80% highway and 20-25% city. My 12 gallon tank lasts me a week. I usually fill up with about 1.8 gallons left.

I average 32-35MPG. Short trips that require the engine to re-warm seem to be the biggest factor. If I end up taking a lot of short trips a week, I get closer to 32MPG. If I pretty much only drive to work, I get 35MPG.

1990 Tercel, 78HP of 1.5L gas sipping goodness. Design defect in valve stem seals; Also doubles as a mosquito fogger.

0-60 in about 20 seconds. :frown:
 

dawks

Diamond Member
Oct 9, 1999
5,071
2
81
Originally posted by: ElFenix
Originally posted by: dawks
Just a quick note, United States MPG are different the the MPG ratings everywhere else, since the US uses their own Imperial Gallon.

the US does not use imperial gallons.


My mistake. Perhaps make an effort to actually correct it in the future, rather then just be a dick or an idiot, whichever.

Anyway:

45 liters = 9.89861208 Imperial gallons
45 liters = 11.8877423 US gallons

There is a difference in what the US uses compared to everyone else. For the OP, make sure you're doing the correct conversion when trying to compare with a US website.
 

DainBramaged

Lifer
Jun 19, 2003
23,454
41
91
Don't listen to the people that say it's cheaper to roll the windows down than run the A/C. Modern automobile manuals now state that it is more economical to use the A/C because of wind drag.
 

doze

Platinum Member
Jul 26, 2005
2,786
0
0
Originally posted by: mcvickj
What is consider a good PSI for proper tire inflation?


not sure if this was already answered yet but check your door sticker for recommended PSI
 

Viperoni

Lifer
Jan 4, 2000
11,084
1
71
Assuming you're calculating in imperial gallons (1gallon = ~3.8L), your mileage is fine for a saturn.

I've never cracked 25mpg highway only.... but then again, I've never been easy on the gas either ;)
 

0roo0roo

No Lifer
Sep 21, 2002
64,795
84
91
Originally posted by: DrPizza
Originally posted by: mayonnaise
Originally posted by: fLum0x
dont floor it every time you go somewhere, dont hold down the gas when you see a red light up ahead...just coast, put the windows down. all three of those should help you. The first one is more or less driving casually and with a cruise as much as you can.


Do NOT put the windows down. It kills your aerodynamics and the airflow etc etc. It was proven on The Mythbusters. Windows up = better MPG.

Sorry, but very little is "proven" on mythbusters. It's a show for entertainment. Also, at lower speeds, air resistance is all but negligible. (Make a giant cardboard car, run down the street with it. A little air resistance. Now, push the car. See how much harder it is to push the car.) Compare the air resistance to the resistance of pushing the car.


well they did show the difference ac on/off on a truck. course on a car thats more aerodynamic i'm not sure at what speed air resistance would be more than ac power. u'd have to do some testing or get info from manufacturer.