MPG Mods

The Yokohama AT's are really solid off-road and also have a very MPG friendly pattern for the highway.

 

When I used mine, I just gave it a very light vacuuming with a SOFT brush attachment, about every 20K. Don't use to much pressure, as you do not want to make any holes in the media.

If you saved your old paper filter, you can lightly rinse the AFE and let it dry overnight, and use your old paper filter till it dries.

 

Great idea, thanks for the info. I didn't keep the old one so I would just let it dry over night, I just dred putting the lid back on the box that houses the filter... the holes didn't line up so you have to really fight with it.

 

I have the AFE ProDry S filter, and it drops into the factory housing exactly like a factory filter. Should go in just as easily.

 

^That is good to know.

As for everyone talking about he Pro-Drys, I heard after the normal filter life (15-30K?) That they can't be cleaned well enough (particles) to outperform a stock air filter. Is this true?

 

My 08 DBL Cab Prerunner consistantly only gets about 18.8 MPG. or about 350 miles before the light comes on. When I bought it two years ago I was getting about 22 MPG. I also took out my performance intake after a month becuase that was getting me about 15.8 MPG. But now with only a 1 mile commute to work I put it back in. Going to wait till tax return time to give her a big tune up.

 

Your intake took your MPG down? And I am getting 28 HWY but I have not changed my spark plugs yet.

When I replaced my air filter, the MPG didn't change at all, actually if anything it hit 28 MPG less often on the UltraGauge (But that is unmeasurable)

My old filter was COVERED top to bottom in dust. So I can see the replacement being good or bad.
Good: More air to the engine=more power=less gas consumed
Bad: More air to the engine=more fuel to maintain air:gas ratio

Can anyone verify what theoretically should have happened?

 

The engine runs in closed loop almost all the time, meaning the air:fuel ratio is always set by the computer regardless of how plugged the air filter is.

As long as the truck has enough power to stay in closed loop (oddly enough, on the 2.7 this is basically any throttle under 4500 rpm), the air filter will have zero influence on mileage.

This is true with most any vehicle as the throttle plate is a far far greater restriction than an air filter ever is.

 

Funny how this thread keeps returning to the air filter that can't make any difference in mpg as you say.

I'll post this again for anyone that wants to know the truth, based on laboratory conditions and rigorous testing conditions.

http://www.fueleconomy.gov/feg/pdfs/Air_Filter_Effects_02_26_2009.pdf

Summary:

Results show that clogging the air filter has no significant effect on the fuel economy of the newer vehicles (all fuel injected with closed-loop control and one equipped with MDS). The engine control systems were able to maintain the desired AFR regardless of intake restrictions, and therefore fuel consumption was not increased.....Closed-loop control in modern fuel injected vehicle applications is sophisticated enough to keep a clogged air filter from affecting the vehicle fuel economy.

This applies the same for a less restrictive filter that lets more dirt in.

 

Yep...

IMO it's best to go with the Denso filter from the dealer, at $17 it's pretty well the least expensive one out there, and it's an excellent unit.

 

Yeah I just bought a cheap OEM. I buy OEM air filters, oil filters, and spark plugs. I believe they designed it well enough. Of course though that doesn't apply to everything.

So what is the difference between a dirty and clean filter? If it has no effect on mileage (Does that imply power? Does that imply engine health?) what is the purpose of changing it?

 

I change mine every 60K. Toyota says 30K. You might lose a few HP near redline, but not at part throttle to 2500 rpm or less that I drive.

Dirty paper filter actually traps more dirt than brand new filter.

 

Sounds legit. I am never above 2000 RPM. Question: Since the truck never goes above 2000 RPM (I drive very conservatively to try and beat my own MPG records), do I ever need to drive it all-out? Or is it safe to only ever keep it at a very low load?

 

I haven't found the need to "blow out the carbon" in 80K.

 

And does your opinion of air filters mirror that of aftermarket intakes? Exhaust? What do you think about those things? For me, I am not interested in the power part being that I am never above 2K. I am also not interested in losing low or top end power, and it seems the only reason for someone like me to alter the exhaust or intake without having a s/c is for sound or looks.

 

Long time lurker first time poster. I've gotten lots of good info here so thanks for that.

Also lots of good stuff here about getting better mileage but it starts with better driving habits; drive like a cheapskate. The only 2 things I can add are: you get 0 MPG while your truck is idling so don't start it until you're ready to drive away and every time you hit the brakes it costs you mileage.

 

Welcome then! And I would like to add: while it is desirable to idle as little as possible, it is important to give jour truck about 30 seconds for the engine to lubricate properly before putting in in gear or driving.

 

ive been able to get right at 22 for the last couple months. number one reason i would say is the torque app (like a scan gauge in ur smart phone) before i would (if its was bareable) only run the A/C when coasting and in high gear. i now realize that when ur coasting u burn roughly 10-15% more fuel with the A/C on for example, i will typically get an instant reading of 65-70 mpg coasting but if i turn the A/C on it will drop to 50 ish due to the additional load on the engine that would other wise be at the lowest load possible. Not a huge deal since coasting isnt a big part of my comute but every little bit helps. also ive noticed that it really doesnt matter (within reason) what rpm u run until u get to 5th since ur not going to get decent mileage in ur lower gears anyway. on rural roads ill run right at 2k rpms till i get in overdrive. i figure the quicker i can get into OD the better my overall mpg is going to be.

 

I actually did a test with my ultragauge-average MPG over a 15 second climb to 60, one with faster acceleration and one with slower acceleration. The difference was WAY more than I had anticipated, enough that it made me accelerate much more slowly during my daily drives. As for 75 MPG coasting, ultragauge and scangages read 999 because no fuel is being used. I haven't used the torque app and I'm sure it's great but for just $60 or so bucks the UG has helped me a ton while being user friendly.

 

torque shows that there is .6 ish gals per hour while coasting with A/C off and engine load is usually around 14% and with a/c on it .7-.75 gph and 16/17% engine load. AFR's do top out at 17. something while coasting though but i think its cuz its too miniscule to measure