Am i the only 4runner owner getting 11mpgs?

[CJ3Flyr]

I have to agree with you. It doesn't seem that 5 to 10 mph would kill your gas that much.

It doesn't sound like much but but areo drag increases as the square of speed. Once you hit the "wall" which, to me, seems to e a bit over 60, fuel consumption goes up dramatically as speed increases.

I get amazing mpg if I don't exceed 65.

 

[anotherrunner83]

my v8 will get around 18 - 19 mpg at 82 all day long....17 with this winter mix crap

 

[CAFROG]

I have a 4.7 V8 and best mpg's was 19.3 (calculated by hand) on a full tank but was 95% hwy.

I have read of V6 4th gens getting over 20 mpg on a tank.

You wrote of A/T tires. Are they bigger than the stockers? (265 70 R17) Although you also wrote about this happening before the new tires.

Any smoke out of the exhuast? (blue, white, black)

Bad cat? Bad O2's? Even with no CEL....an O2 could not be heating up correctly and send false info back to the ECU. Smell the exhaust when the car is at running temps.

 

[2004TR4-SR5]

tires are same size

 

[Nuke]

40 PSI in your tires? That's not a good idea as a way to improve your fuel mileage. At highway speeds and 40 PSI, you're tires footprint is diminished and you open yourself up to handling problems.

There are so many variables associated with fuel mileage it's not even funny. I'd be typing my azz off just listing them and I'd still miss a few; any ONE of which can drastically affect mileage the way the OP mentioned. Combine a few and it's simply miserable.

But a few things stand out here as I read thru this thread:

1. Winter fuel blends can cause a drop of 2 MPG or more. For a 23 gallon tank, you lose close to or over 50 miles/tank.

2. The percentage of ethanol from station to station and even at the same station from delivery to delivery can change drastically enough to cause a 4 MPG drop. Again, that's close to 100 miles/tank.

3. Nowhere have I read what the OP's mix is of city vs highway driving and if any hills are involved. My fuel mileage drops at least 2 MPG between dead flat terrain and even moderately light hilly terrain.

How about forgetting the apps and ignore the wildly inaccurate on-board and begin hand-calculating?

 

[Ducman]

Mpg

I think the reason for your poor MPG is listed in your sig. :shrug:

You have a ton of high drain electronics on your truck! That power has to come from some where. Your alternator generates power by causing parasitic drag on the crank which will almost certainly lower your mpg.

 

[Nuke]

I think the reason for your poor MPG is listed in your sig. :shrug:

You have a ton of high drain electronics on your truck! That power has to come from some where. Your alternator generates power by causing parasitic drag on the crank which will almost certainly lower your mpg.

To the tune of 4-5MPG? I truly doubt that...

 

[Ducman]

To the tune of 4-5MPG? I truly doubt that...

According to his last post:

UPDATE....so after i took out my carbon filter..put a k&n filter in...filled my tires to 40 psi...used lucus fuel system cleaner...replaced my autolie xp iridiums with denso's from toyota....and i disconnected my battery for 10 mins...my mileage went from 11 to 13.67...not where i want it to be but its a start!...thanks for all the help guys!! my next move is probbably just to replace my o2 sensor or sensors and MAD sensor...and maybe a aftermarketCAI or a custom CAI

According to his info, hes in Havertown, PA (as of this post 30 deg) which means hes using winter blended fuel so hes already taking a MPG hit there. He did not say what % of his recent driving was city/highway so I'll assume 50-50 there.

How is that a 4 to 5 mpg deficiency? He said a few pages back

note..my avg is 13.72 but that is still low

I'm saying his super stereo setup, alarm and lighting upgrades could easily give him a 1 mpg hit or so which combined with some city driving, cold weather and winter fuel blend would be about right for where he is currently.

He also mentioned owing a 2001 cammed camaro so I'm going to guess he may like to get on the throttle a little bit too which makes for less than ideal MPG.

Nuke-
I just noticed you've got an 07 GT! Nice, I've got a 00GT with a Kenne Bell. I've got a buddy with a 06 and the thing handles so much better than mine.

 

[2004TR4-SR5]

my driving is like 70 highway and 30 city...and this problem happened long after the electronics were put in...ive never heard of anything like before..and i do not drive my truck hard..i really dont drive my camaro too hard either

 

[chayos00]

my driving is like 70 highway and 30 city...and this problem happened long after the electronics were put in...ive never heard of anything like before..and i do not drive my truck hard..i really dont drive my camaro too hard either

Dude, I'd say you have checked about the most obvious things. Like some have mentioned, check for dragging brakes, somehow your exhaust is getting clogged..... IDK. I don't remember if you mentioned fuel filter? Just a thought.

Your electrical system won't make a big hit on your MPG with what you have. I have a 600W stereo in my truck plus a higher output head unit. Didn't notice even a 0.1MPG difference. Also true HID lights are usually 35 watts versus, halogen @ 55w or 65w.

To the guys who say it's his lights, why else would Toyota put HID's in their Prius.... less electrical drain.

 

[Ducman]

Stereo

Just repeating what I've read other places about parasitic drag from high amp electrical systems. I just happened to lump 'lights' in with the rest of the electrical upgrades in his sig.

As stated ... all the other standard obvious causes have already been listed.

To the OP, do you let your truck warm up in the morning? If so that could be effecting your calculations too.

 

[2004TR4-SR5]

not too long...i start it like 2 mins before i leave

 

[05 4runner]

Did you get anywhere lately? I believe from what I've read you stated you have bigger tires? If you don't then disregard what I'm about it say.

I purchased my 05 4runner from Toyota with approx 42k on it. From that point to about 70K (yr and a half) my averaged MPG was 24. This was 70/30 has well (HWY/City). Once I installed my 3" lift and bigger tires (see sig) I shortly later noticed my MPG's went way down. My MPG's are around 17 now. I thought some thing was wrong and I needed a tune up so I did all the basics besides the oil which I knew was good. Note I use OEM plugs, filter, oil filter (all from Toyota) and Mobil 1 or Castrol 5w 30 synthetic oil. Well nothing changed. It wasn't till recently after reading on here that I come to the conclusion the massive drop was due to my lift and/or bigger tires. MY GYSA's are ok, but not impressive. They got around 10k on them or so and appear to already be approacing replacement. Even tho it will look funny having the lift and small tires I think I'm going to go back to oem size tires. Not those sh**ty dunlop AT20's, but a really good all season. I just picked up some sweet wheels/tires from a buddy anyhow that I figured I could swap on during the winter and when I go to Rausch Creek. Haha enough of me. But you might be experiancing a big dip in MPG's due to your tires!

Judd

 

[KB084RUNNER]

It doesn't sound like much but but areo drag increases as the square of speed. Once you hit the "wall" which, to me, seems to e a bit over 60, fuel consumption goes up dramatically as speed increases.

I get amazing mpg if I don't exceed 65.

+1 I get about 22-24 at speeds up to 65mph at 70 it drops to 20mpg at 75 drops to 19mpg.

 

[KB084RUNNER]

If you want to calculate average mpg accurately then do this:

Fill your tank once and record gallons added and odometer mileage.
Drive until 1/8 of a tank.

Add exactly 15 gallons of gas (do NOT top off tank) and record mileage
drive until 1/8 tank

Add exactly 15 gallons of gas (do not top off tank) and record mileage
drive until 1/8 tank

Repeat 5 more times.

Now sum all gallons & miles and divide the miles by the gallons.

You will have an accurate reading of your actual mpg.

Every fuel filler nozzle clicks off at a different pressure. They are supposed to be close but you can have as much as a 1 gallon variance depending on ambient temperature of fuel, air and the age of the nozzle etc.

Adding a specific amount of fuel is the best way to get a real accurate reading versus topping off.

 

[mcflavin]

the app is called carminder...it keeps track of maintenance and warns you when its coming up and also has a gas log and very accurate....anyways...i just rotated my tires..filled them to 40 psi...put a k&n air filter in...took out the hydrocarbon filter...and put lucas fuel system cleaner in...as i filled up with gas i pull the ects fuse and the 2 efi fuses and disconnected the battery.....after all that i started my truck and the computer range went back to 395 miles and my avg mpg is now at 17.7 after a small highway drive...needless to say its back to where i wanted it..but lets see how long this lasts. . .i will update what my iphone app tells me on my next fill up!!

I am afraid the whole problem is that you are computing gas mileage by the "range." Range is performing a predictive model. That is not a reflection of your mileage, nor is it even a prediction of your mpg.

 

[2004TR4-SR5]

im not doing it by range nor do i have bigger tires..tires are oem size...i kno the range is full of sh.t anyways

 

[lVlAXX]

Hey man i have a 2003 v6 and am having the same issues as you. After i put the K&N in got about 25mpg, then dropped to like 19-21, after a few months im down to idk 12-14. ive tried everything except the brakes. i'm gonna check that out next.

 

[krravi]

I used to get 400 for a tank and now i get around 365 standard. But i think thats due to the winter fuel blend and increasing levels of ethanol in the gas these days.

 

[OKBrian]

Did you notice this drop in mileage after the spark plug replacement? I have a 2004 v6 4x4 and I get 16-17 in town and have gotten 23-24 on the hwy (all highway on a long trip). I once had a 1996 v6 4runr 3.4L 4x4 and replaced the spark plugs with the wrong ones. My mileage dropped by 4miles per gallon.