21 MPG whats wrong

[P205]

I have a 2008 yaris sedan Automatic 100% city driving

afe intake
new spark plugs
tightly inflated tires
I drive like a little old lady
usually im the only passenger 155 pounds
I cleaned my maf sensor,made sure it was sealed well
no AC
i don't let it idle for no reason
I feel like im doing everything i can possible do right but still
all summer iv been getting 21 mpg, winters here and im lettting it warm up for about 2 mins still 21mpg

[Altitude]

Start with the easiest...

How did you arrive at the number? Do you have a scangauge or similar? Are you sure you're using the right values in your calculation?

[P205]

i am getting 218 miles to my tank. on a 10 gallon tank

[jpmck03]

You completely filled the tank with exactly 10 gallons on your last fill-up? Methinks you are messing up some math there or goofed on something or another...

[Kar98]

You completely filled the tank with exactly 10 gallons on your last fill-up? Methinks you are messing up some math there or goofed on something or another...

Give the man some credit. I'm sure he's able to divide a three digit number by ten. My bet would be with bad gas.

[P205]

Im lost, dosent this seem like bad mpg for my situation? i use sevral diffrent gas stations around

[rningonfumes]

How many tanks of 21 mpg have you been getting?

[P205]

i have had maybe 8 tanks through it since I've owned it

[tooter]

Just for fun... I'd try disconnecting a battery cable for a few minutes so that the ECU can go dumb, and then reconnect, fill up, drive normally, log your mileage for a tank and see if there's any change.

This is an easy test that costs you nothing. :smile:

[NEexpat]

Well.................

This is a real head scratcher................21 mpg is about half of what I get in the summer. From your posts I am gonna guess you are not driving around in 3rd instead of drive, also gonna guess you are not leaking fuel anywhere. If it were an isolated incident I would have guessed maybe someone is pulling your leg and stole some gas out of your tank.
Unless it is somekind of ECU problem like tooter said,.................. but boy 21mpg.

Wish I had a suggestion for you, good luck.

[Altitude]

Im lost, dosent this seem like bad mpg for my situation? i use sevral diffrent gas stations around

Yes, that is horrible MPG. It's 1/3 to 1/2 less than the norm. You might have a leak or as NEexpat said, someone might be siphoning it out of your tank.

Take it to a shop and have them hook up a scanner and check for any codes.

[jpmck03]

Give the man some credit. I'm sure he's able to divide a three digit number by ten. My bet would be with bad gas.

:rolleyes:

I wasn't trying to suggest that he was a complete dolt or anything like that... just that maybe he transposed a number or something when he was doing his arithmetic.

I know I've done it before...

Hopefully, P205, you get it figured out!

[alpha1]

City driving would be for the average city driving. Ex. of others experience with a yaris http://www.fueleconomy.gov/feg/Find.do?action=yourMpgVehicle&id=25894
Perhaps your city is not average and very very congested with backups due to airports etc. making you sit and idle on the road.
Many variable like warm up/ idle time/ sitting in the car running the heater/ac listening to music/ foot riding the brake/emergency brake on/ air filter needs to be cleaned/

If above is good, definitely inflate your tires to a higher psi if possible; empty excess weight from the vehicle; check for other maintenance issues.

Other good idea: http://www.yarisworld.com/forums/showthread.php?t=39818

[rningonfumes]

Okay, something is really wrong in my opinion. Most of us would have to gun it and all out throttle every where we go to even touch 30s.

How short are your trips? You may be letting it warm up for 2 minutes but you are in Alaska. This is summer numbers for you? Really short trips combined with low temperature climates might show that your engine isn't warmed up at all and you're constantly driving with the engine trying to warm up.

If it is the case that you have really short trips, for one tank try going on longer trips.

I'm also going to ask some very stupid questions not saying that you are necessarily the stupid one. We've had to ask this before to others:
1. Are you sure you're not driving in 3rd?
2. Are you sure you're not driving with the parking brake on?
3. Does the cold engine light actually go off?
4. How old lady is your "old lady driving?"

Sounds like you're doing everything right so far.

[e39a]

Tire size? Cylinder compression issues?

[P205]

my trips are very short 2 miles to work, 2 miles to the girlfriends house.
When you say driveing in 3d. it shows d3 on the trans switch so i put it on D3
its an automatic cold engin light usaully i drive when its out. half the time i take off when i think its about warm to go then the light gose out before im out of my street
and for driveing like a old lady. i take of very slow at every stop never accel fast. never hit over 45

[rningonfumes]

That'll do it. 2 miles is very short.

About the driving in 3D.... One side is D ( all gears to include 4th) and one side is 3 for 3rd gear. Are you sure you're on the "D" side. Again this issue has come up before with people not familiar with gated shifters.

I'm going to call it on the 2 miles. To be sure, try going out for a longer distance for just one tank. This means pulling in 5 + miles on work (to and from) and the girlfriend's house (to and from).

[P205]

allright i have been driveing in 3 this hole time

[rningonfumes]

Okay, drive in D for a tank and report back. I suspect it'll only improve a bit. And drive like normal no adding miles. We want this to be somewhat scientific ie testing only one variable at a time--- the D vs 3rd gear driving.

To comment on my " I suspect it'll only improve a bit". ---- This is because if your car is still "warming up"....it won't shift higer than 3rd gear. *I need someone to back me up on this because I have a manual and am relying on memory from previous member's threads/posts.

[Kar98]

allright i have been driveing in 3 this hole time

And driving no further than three miles? AND letting it warm up for three minutes before driving? Yeah, that will do it. Mystery solved.

[b20vteg]

allright i have been driveing in 3 this hole time

not to be rude, but:

http://digboston.com/wp-content/uploads/2012/01/facepalm.jpg

[henrylee]

Lol not to be mean but fail...

[charles nelson]

I have a Scangauge II. I let my brother-in-law borrow my Yaris for a week. He complained that he was only getting about 25 mph. When he returned, I had him take me around the block. He put the automatic right into D-3. I pointed out to him that was setting the trans into third not higher gear. He was ticked off that the shift mech was so poorly labeled.

[NEexpat]

I was guessing you were not in third.

Not uncommon, I am currently helping my niece practice for her driving test next month and she often "slams" it into 3rd like Frank Bullit before we get going.

Short trips, cold weather, + the cold engine shifting restriction. Well you were always in 3rd and never going to get out of it.

Hopefully that's it. Keep us posted on your mileage.

cheers.

*Usually takes me about a mile or two, before my automatic is allowed to up shift in the winter, shorter in the summer.

[P205]

Who has a scanguage? is it just plug and play? where can i get one

[P205]

Great thanks for the reply, I will now being driving in D " not drrrrrrrrr"
I drive a manual truck all my life, then i have to learn to drive automatic lol

Ill post results soon

[NEexpat]

You can buy a Scangauge II online.

It plugs into the OBD port.

I personally use an UltraGauge. I prefer it aesthetically, but mostly because I'm a cheap bas.....well anyway.

[P205]

Update. so I have been driveing in D now. its looking like no change, when my first bar from my gadge gose away i have gone 45 to 47 miles witch is what i have been getting when i was driveing in 3

any ideas?

[rningonfumes]

Read my posts again about the cold.

[P205]

yea. humm . i was getting the same mpg in the summer. my cold temp gose out before i leave my street

[NEexpat]

Forget the bars. I've had my first bar drop as low as 61 and as high as 92. Go by the pump and the miles.

Suggest if you have the time, money and inclination. Fill your tank, set ODO A to 0.0 and go for a long sustained drive at speed, 65 etc. And by sustained I mean several hours, at least 3. Then go top of the tank and see how it went. If you have cruise control lock it in. See if you get in the mid to upper 30's.

I can't believe you're not going to see improvement by just getting out of third. I think the short distances and the temp affect more than anything. I wouldn't be surprised if you got into the low to mid 30's from your city driving.

cheers.

[jambo101]

I have a 2008 yaris sedan Automatic 100% city driving

afe intake
new spark plugs
tightly inflated tires
I drive like a little old lady
usually im the only passenger 155 pounds
I cleaned my maf sensor,made sure it was sealed well
no AC
i don't let it idle for no reason
I feel like im doing everything i can possible do right but still
all summer iv been getting 21 mpg, winters here and im lettting it warm up for about 2 mins still 21mpg

I think your mpg calculations are off as if there was a problem that gave you that much of a MPG decrease from normal a check engine light would surely be on.
My 08 sedan is mostly driven around town and i get around 500kms/300miles per tank which i think is in the normal range.

PS isnt it an 11.1 gal tank?

[P205]

humm who drives in cold weather here

[yarisugi]

You're right Jambo – 11.1gal tank. That translates to 19mpg – SUV territory. lol.

Other options:
1) Commute is two miles - sell your car, ride a bike.
2) Remove your interior, leave the driver's seat.
3) Replace air in tires with helium. It really works!
4) Get rid of the decomposing corpses in your trunk.
5) Lose the girl, save two miles.
6) Lose weight.

All jokes aside, at least you're driving in "D" now.

[P205]

lol well if i was any lighter float to work. but anyways i guess im just screwd

[NEexpat]

Seriously, go for a long drive and see what your mileage is.

This will give you some indication if it just your particular commute circumstances or if there is truly something wrong with your car.

And if you mean screwed by owning one of the most reliable and dependable cars on the road today, then we are all screwed.

[P205]

what NEexpat seems to make sences

[Kaotic Lazagna]

Yeah, when the engine is cold, the ECU runs pig rich. On my Scan Gauge, it'll read on average in the teens and low 20's, but then again I have a heavy rim/tire combo. But with that being said, even if I'm smashing on the gas all day everyday, I'll still be in the low 30's mpg.

And with that being said, I'll say check your tire pressure and make sure it's 32 psi at the lowest (I drive around at 51 psi), and check your alignment. Those two can really kill your mpg's.

[P205]

I have my psi at about 46 and the car drives straight as an arrow,

[Kaotic Lazagna]

hmmmm, I would have your brakes checked. They might be producing too much friction, causing your engine to work harder to get the car to speed and to maintain speed. If your tire pressure is high and your alignment is within manufacturer specs, you really shouldn't be having mpg issues.

So have your brakes checked, change your spark plugs, and change your intake air filter. Also, if you are using cheapo gas, I'd suggest switching to a top tier station.

[P205]

I have gotten new spark plugs, what you you guys prefer ?

[Kar98]

I have my psi at about 46...

That's a lot. :eek: I'd stick with 32.

[charles nelson]

Popular Mechanics had an article about tire pressure and mpg. The manufacturers recommended pressure is designed to put the least wear on the suspension. Significantly higher tire pressure will increase your mileage (less road friction) but will greatly increase suspension wear. So with higher pressure you get better mileage and lower fuel costs but higher repair bills later on.

[caineroad]

it is possible... translate into km that is 350km. On my yaris, i fit it with mini cooper 17" wheels(heavy) and now i've lost 30km on a full tank.

I drive 50/50 city and highway, and I am only getting 430km, then the fuel light flashes, about 9.4L/100km.

so basically if I were doing 90-100% city, it is not surprising to get 350km(218 miles)

if you do the math, or just google look it up my numbers translate back to your mpg or miles, you will get an idea.

my car is completely stock under the hood.

[P205]

well i find it odd because looking at the mpg people are getting in the forums, a lot of them are getting Lazy 30mpg all city driving

[Kar98]

well i find it odd because looking at the mpg people are getting in the forums, a lot of them are getting Lazy 30mpg all city driving

Yeah, city driving, I'm driving 17 miles to work in one rather large city. Not three miles, and letting it idle for two minutes. I'm surprised you're even getting 21 mpg.

[tooter]

it is possible... translate into km that is 350km. On my yaris, i fit it with mini cooper 17" wheels(heavy) and now i've lost 30km on a full tank.

I drive 50/50 city and highway, and I am only getting 430km, then the fuel light flashes, about 9.4L/100km.

so basically if I were doing 90-100% city, it is not surprising to get 350km(218 miles)

if you do the math, or just google look it up my numbers translate back to your mpg or miles, you will get an idea.

my car is completely stock under the hood.

You just implied another variable that no one seems to ever mention:

Wheel Diameter

Almost everyone here runs different diameter rims combined with a wide variety of different sized tires...

...and yet no one seems to be factoring in their wheel diameters to adjust their odometer readings to arrive at their actual gas mileage.

I changed my rims and tires just like everyone else, except I used a wheel diameter chart to determine the tire size and aspect ratio so as to keep the diameter within 1% of the stock diameter so that my odometer continues to give accurate readings. :smile:

[P205]

I wonder if by city driving people are in the city on the highway long trips at high speeds, when i say 100% city driving i mean stop lights often

[tooter]

I wonder if by city driving people are in the city on the highway long trips at high speeds, when i say 100% city driving i mean stop lights often

I know what you mean. I often drive in traffic for long periods of time. My last fillup was only 36mpg. The computer showed the overall average speed for that fillup was only 7 mph! :laugh:

[jambo101]

Something aint right try some of the obvious fixes then i'd say it would be worth your while to take it to a reputable garage and get it fixed..
http://www.carsdirect.com/car-buying/8-main-causes-of-bad-gas-mileage

[OTA'sTOY]

OP did you change your oil lately?

[P205]

yes i did, 5w 30 royal purple

[Martinezn.964]

Original Intake gets you better gas milage. Try it

[Martinezn.964]

Also check alignment

[frownonfun]

My mileage has never been all that great either. But I think the city of Odessa (since it's an oil town) actually constructs everything in such a way that people use as much gasoline as possible. Ok maybe that's a stretch but seriously the civil engineers around here must be bottom of the barrel because the traffic here is a nightmare and shouldn't be for a town of this population. Maybe you are in a town that doesn't have anything set up very well either. Just try driving a Tundra that gets 12mpg around for a while and then you'll love your 21mpg.

Like seriously if there is an intersection in this town without a stoplight i'm sure they are working on putting one up right this very moment. And god forbid you ever make more than one green.

[caineroad]

You just implied another variable that no one seems to ever mention:

Wheel Diameter

Almost everyone here runs different diameter rims combined with a wide variety of different sized tires...

...and yet no one seems to be factoring in their wheel diameters to adjust their odometer readings to arrive at their actual gas mileage.

I changed my rims and tires just like everyone else, except I used a wheel diameter chart to determine the tire size and aspect ratio so as to keep the diameter within 1% of the stock diameter so that my odometer continues to give accurate readings. :smile:

Good job you brought this up... i didn't realize that.

Ever since I changed to 17' Cooper S rims, my speedo is slower than actual speed. Therefore the distance counter must be also slower (less), that would make sense to the loss mileage!