Hi guys,

Im in need of some help over something thats been bothering me...I own an '04 scion xb, and i cant seem to get anything past 28 mpg HWY!., 26 mpg on average.... Ive always put this issue aside, but with gas going up, and my new job causing me to carpool, yet drive 210 miles there and back once a week, getting 28 mpg isnt cutting it for me..

for example, on my turn to drive the carpool, i spend a total of about $31...yet when my friend drives his 4.6L V8 Mustang, he pays $36 !....cmon now...

I need to change my fuel filter, ive been too lazy with it, and being @ about 110,000 miles dont help without changing it...oil has been changed at the right times, cleaned air filter...so maybe this is part of the issue...

i also believe this is a power problem, since i find myself @ 4.5-5 k rpm most of the time trying to accelerate, go up hills, or have 3 people in the car....maybe a suggestion to give a bit of UMPH to the car to keep at lower rpms?

Any ideas? suggestions?

HELP!...

 

i was getting 28mpg consitantly, then switched to NGK irridium spark plugs and now average 30mpg. i have a intake, header and exhaust, which gives it a little more poop, I'd get even better, but i have a hard time keeping off that skinny little pedal.

 

i actually switched to those same spark plugs a long while ago...yet i remember a that compared to what i saw here and what napa suggested there were different spacings used...im going to check the spacing this weekend too then along with the fuel filter...

what spacing should i use?

 

they are pre-gapped at .044".

 

You still want to check each one and adjust if necessary though.

 

cool thanks, ill check them this weekend...

but i still wonder if it can be something else....hmm..

 

driving habits MUST play a factor here. focus on NOT coming to complete stops as best you can. Play driving like game. but take it serious of course! avoid complete stops at all cost. cruise control it at 62mph or so and don't insist on overtaking other cars. if you can maintain self control and not accelerate fast, dont ever go over 65mph, try to keep it at 60 on the freeway (yes while everyone blows by you insisting 70 isn't even fast enough for them), and avoid complete stops like the plague. im willing to bet your fuel economy increases.

 

This.

Driving habits are more important than anything. Just sticking to speed limits is good for a few mpg, even if it drives everyone else crazy.

Another tip-- when accelerating, get to your top gear as soon as possible. I actually floor it, but shift at 2-2.5k, and can get almost 35mpg around town. I'm also in 5th gear at 35mph, and don't find myself accelerating slower than traffic in general.

Yet another tip-- drive like you don't have brakes. Maximize coasting and engine braking, and anticipate lights on familiar routes.

 

And turn off the AC! My most recent tank took a mileage dump after 3 days of mad heat/humidity.

Running the AC kills mileage.

 

I'm sure you have already thought of this but jic you haven't, check your tire pressure. You'd be amazed at how big of a difference even a couple of psi can make. I don't know much about them but, grounding kits and voltage systems claim to increase mpg. Anybody have any feedback on whether they work as promised?

 

From my readings here, I increased the suggested COLD tire PRESSURE by 3 Lbs. in each tire.
- Tire wear has not suffered.

 

Does anyone know the maximum PSI the stock tires are rated to handle?

 

Sounds like you found all the reasons for poor mpg.

 

It's stamped on the tire.

 

you should do better than that with a few things mentioned above I am getting 38MPG on my last 3 tanks

 

x2 You can't expect to get good mileage if you are consistently winding it out.

 

You have to do the opposite -- keep the throttle and rpms as low as possible. I just filled up after 200 miles of suburban driving. The pump clicked off at 5.3 gallons = 38.1 mpg. This was a couple mpg better than I usually get, but then I have begun immediately turning the engine off when it looks I will be stopped for more than a minute. I shift at 2000 rpm, and cruise in 5th around town at 2000 rpm, and do not use acceleration, which are the three main tips for good mpg.

 

when was the last tune up?

 

i havent got a tune up, i check the car myself....i got NGK irridium plugs probably over 20,000 miles ago yet they say those go on for a very long time...cleaned my air filter, changed my oil (synthetic btw)...and im going to change the fuel filter this weekend..

 

Depending on how bad your commute is, 26-28 MPG may not be unreasonable. I take everyone's claimed gas mileage with a grain of salt. I've heard too many people making outrageous claims (not here of course) about how great they can drive and get super gas mileage. I know the xB is capable of getting great mileage under the right conditions. I've gotten 40+ MPG driving on the parkway and 35+ MPG driving half on rural roads and half @75+ MPH highway with the A/C cranked. But my commute is almost always a parking lot and the xB will get 25 MPG, +/- 3 MPG.

You shouldn't be regularly having to drive at 4.5-5k RPM. Passengers will definitely weigh you down but it should have adequate power around 3k-3.5k to make it up hills.

Try increasing the tire pressure a little. I run mine at 32-33 PSI all around. I don't like the ride if I go any higher. Check for uneven wear, a bad alignment could also hurt your mileage.

Try taking the snorkel off the airbox if you haven't already. That should give you a little more power at higher RPM. Since you said you cleaned the air filter, I assume you have a K&N or some other reusable filter. Make sure you don't over oil it (if it's one you oil) because that would make it more restrictive and get oil on the MAF sensor.

Try gas from a different station if you've been getting worse mileage without any other changes and usually fill up at the same one.

Synthetic oil is great and all, but I don't think you'd see a measurable difference in fuel economy. A lighter weight oil (5w-20, or a mix of 5w-20 and 5w-30) might increase your fuel economy by 1 MPG or so.

Run the A/C in recirculate. Should stay cooler and make the compressor run less. Tinting the front windows would also help keep it cooler so the compressor would run less.

And, of course, smooth driving. No quick starts or stops. In traffic, do like the truckers and just try to keep rolling.

Otherwise, you'd have to start looking for problems. At 110k miles, the MAF could be dirty and throwing off the air/fuel mix? Clutch or transmission slipping?