Xb *really* should be getting better MPG (about 26.7 right now)
 

I drive a 2006 Xb that was purchased used just a few months ago. This is my first Xb, so my comparisons are essentially nil...except that it seems I should be getting better mileage: I was at 26.7 after my fill-up yesterday. Sad :(

A few things worth noting:
- My Xb has 77k on the clock
- Car originally came from California (I'm in Washington State)
- I drive conservatively, and almost always without a lead foot, A/C, or windows down
- Running 15" Konig Backbone wheels that are lighter than stock
- Just about 2k on my tires, inflated to 38 psi
- Air filter is new
- Plugs are new and properly gapped (NGK Iridium)
- Just cleaned the MAF sensor
- Running 5w30 dino oil
- A lot of my driving is a 30-mile (15mi x 2) commute on the freeway

So, where should I look next? O2 sensor(s)? Fuel filter? Take it in for a tune-up? I don't need to get 40mpg on my Xb (It'd be nice!), but I feel like I should at least be getting 30mpg+

Help!?!?

Yip

This is a tough one. You should be doing better than that. Low to mid 30's if anything. Was it getting better mileage before? Or is this the first time you checked it? How did you come up with the figure?

Over inflating your tires might save a little gas, but will contribute significantly to uneven tire wear. The fuel saving may or may not offset the cost of a new set of tires. I run mine at 32/32 F/R, but I have my car outfitted with significant amounts of weight (~700lbs of audio equipment). I also live far up a hill, about 1.75 miles of steep grade. I return around 21-22MPG.

I've been tracking the mpg since July. Never seen better than 30 (more like 29.8), and I typically get about 27-ish. No change thus has really improved it at all.

I check my mileage by filling up fully, zero out the tripometer, drive until mostly depleted, fill up fully again, and then divide my fill up gallons into the tripometer miles. Pretty standard.

Ideas for me?

Is it auto?
I live about 25 miles east of Seattle, in the village of Duvall.
I get 28-30 MPG in my auto Xa.
Hills in Seattle are not best friends for such an under powered car.

I use HEET (red bottle) every other tank fill. I'd also suggest to try some injector cleaners such as BG44K to see it helps improve thirst.

If your getting 27-30 as an average that's pretty standard
If your 15mi x 2 is rush hour stop n go traffic your doing fine.

I get 28-30 average around town, if I go all freeway for say 50+ mile trip I can get 32-34mpg

It is an AUTO. I should've mentioned that.

Yeah, hills aren't great...but I'm not hitting many hills in the part of Seattle where I work (nor in Edmonds, where I live).

Heet or injector cleaner probably couldn't hurt...but how many MPG difference could it really make?

I guess that's what I'm trying to discern. Some folks will say "yeah...27 or 28 is just about right", whereas others seem to say that they get 30mpg no matter how they drive, or what they do. I've had a couple of weeks where I was making many long trips -- 60 mph or so, most of the time -- and really trying to take it easy. I expected much better mileage, only to find that I got 28mpg at the next fill-up. Kinda disappointing. It seems like I should be doing better on average.

On average it takes at least couple of dozens of consistent fill ups to approach a non-scientific MPG calculations. But some of us tend to exaggerate performance based on few and far between data inputs.
I'd suggest not to take it too serious as your real worlds MPG is about as accurate is it comes.
Toyota emission strategy is based, much like any other manufacturer, on Lambda sensor data. If something were to happen with that data, you'll be notified via MIL light...
If your car's engine is up to tune with OEM or better parts, it should be at its peak performance.

cheers...

If I drive one full tank at these speeds, these are my MPGs:

80MPH: 22MPG
75MPH: 25MPG
70MPH: 29MPG
65MPH: 34MPG
60MPH: 40MPG

If I do 100% city, I usually get around 22-24MPG. These figures are with an auto with ZERO A/C and cruise control for highway.

You can manage 30+ MPG in the city if you neutral coast.

i get 35 mpgs in the city day in and day out

Yeah....THIS is what I'm talking about!

I rarely drive over 65 mph (usually closer to 60), I'm not a lead foot, and my vehicle is pretty close to stock -- save for lighter wheels, new plugs, etc.. Although I work "in the city", my actual city driving is quite limited.

Anyhow, I've seen *close* to 30 mpg on one tank, but that was with me driving ridiculously conversatively. Otherwise, I'm right around 27/28 mpg at best, and it doesn't seem to vary outside of that range.

It just seems like there is SOMETHING simple that's broken: O2 sensor, fuel filter, flux capacitor, or whatever. Maybe a local shop could help me figure it out? Or maybe that's just throwing money away at a witch hunt....

I'd suggest doing transmission service, check front calipers for drag, rear drums for proper adjustment.
I'd also suggest taking a long ride (over a weekend) to see what MPG you'd get on the I-5. It is much flatter than I-90 and you'd get better picture of your hiway MPG. As for combined city/hiway your numbers are withing normal range.

Curious if you ever got this one figured out. I experienced a decrease in MPG last summer and it turned out to be related to a dirty MAF sensor. I see you already cleaned yours. One thing I noticed this Fall on a trip to AK was that this little engine really suffers on roads with a lot of gradual ups and downs. The Alaska Highway is like that most of the way and I was typically getting about 25 mpg when I would have expected closer to 35. Some of that was probably Canadian gas which I understand has more additives than U.S. gas. Anyway, I was getting worried that maybe it wasn't the MAF sensor until I got back home and discovered that my MPG was back to normal.

I have a ScanGauge installed and so I could see what was happening on the AK Hwy. On the upgrades I was getting 17 mpg or less and then on the downgrades, it varied a lot, but maybe 45 mpg on average. My point would be that since this car is new to you, it might be that the mileage you are getting is about right for the driving you typically do and/or the way you drive in general. I don't have a lead foot, but when I got this car last year, I was getting about 27 mpg combined. Then I bought the ScanGauge and within a couple of weeks I was getting 37. So it payed for itself pretty fast. Added benefit was that I definitely knew something was wrong last summer when my MPG dropped off despite the fact that my driving habits had not changed. For example, I knew that on a trip I take regularly, I usually got about 46 mpg. When the best I could get on that trip was 37, I knew something was wrong.

I put snow tires on 2 days back and I am getting only mid 30's even with hypermiling.