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GX470 Fuel Economy
07-07-11, 10:40 AM
#47
http://www.usatoday.com/money/autos/...emiumgas_x.htm
This article may explain why 4runners V- 8 gets a different fuel recommendation in their manual than the corresponding GX470.
This article may explain why 4runners V- 8 gets a different fuel recommendation in their manual than the corresponding GX470.
07-07-11, 11:47 AM
#48
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http://www.usatoday.com/money/autos/...emiumgas_x.htm
This article may explain why 4runners V- 8 gets a different fuel recommendation in their manual than the corresponding GX470.
This article may explain why 4runners V- 8 gets a different fuel recommendation in their manual than the corresponding GX470.
07-10-11, 11:40 PM
#49
Caution on the k&n air filter, first, it will not improve anything that you can measure on a GX 470, second, the oil from the filter has been know to dirty the MAS (mass air sensor).
A mass air flow sensor is used to find out the mass of air entering a fuel-injected internal combustion engine. The air mass information is necessary for the engine control unit (ECU) to balance and deliver the correct fuel mass to the engine. Air changes its density as it expands and contracts with temperature and pressure. In automotive applications, air density varies with the ambient temperature, altitude and use of forced induction and this is an ideal application for a mass sensor. (See stoichiometry and ideal gas law.)
There are two common types of mass airflow sensors in use on automotive engines. These are the vane meter and the hot wire. Neither design employs technology that measures air mass directly. However, with an additional sensor or two, the engine's air mass flow rate can be accurately determined.
Both approaches are used almost exclusively on electronic fuel injection (EFI) engines. Both sensor designs output a 0.0–5.0 volt or a pulse-width modulation (PWM) signal that is proportional to the air mass flow rate, and both sensors have an intake air temperature (IAT) sensor incorporated into their housings.
When a MAF is used in conjunction with an oxygen sensor, the engine's air/fuel ratio can be controlled very accurately. The MAF sensor provides the open-loop controller predicted air flow information (the measured air flow) to the ECU, and the oxygen sensor provides closed-loop feedback in order to make minor corrections to the predicted air mass.
A mass air flow sensor is used to find out the mass of air entering a fuel-injected internal combustion engine. The air mass information is necessary for the engine control unit (ECU) to balance and deliver the correct fuel mass to the engine. Air changes its density as it expands and contracts with temperature and pressure. In automotive applications, air density varies with the ambient temperature, altitude and use of forced induction and this is an ideal application for a mass sensor. (See stoichiometry and ideal gas law.)
There are two common types of mass airflow sensors in use on automotive engines. These are the vane meter and the hot wire. Neither design employs technology that measures air mass directly. However, with an additional sensor or two, the engine's air mass flow rate can be accurately determined.
Both approaches are used almost exclusively on electronic fuel injection (EFI) engines. Both sensor designs output a 0.0–5.0 volt or a pulse-width modulation (PWM) signal that is proportional to the air mass flow rate, and both sensors have an intake air temperature (IAT) sensor incorporated into their housings.
When a MAF is used in conjunction with an oxygen sensor, the engine's air/fuel ratio can be controlled very accurately. The MAF sensor provides the open-loop controller predicted air flow information (the measured air flow) to the ECU, and the oxygen sensor provides closed-loop feedback in order to make minor corrections to the predicted air mass.
I have actually noticed a very slight MPG improvement with the KNN CAI on the GX. But nothing to really get excited about. It's a truck, expect low MPG.
Also, the on board computer averages out the MPG since you last reset it. So if you reset it, it will give you current results instead of averaging over many more miles.
07-11-11, 06:33 AM
#50
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Thread Starter
Update: 360mi/24.3gal tank AND diff beetwn older 14mpg /newer 16mpg GX's = $1.30/tank
Hello all,
contrary to a post from a couple of days ago which warns about overfilling the tank, I figured that nothing had ever happened, yet my range was much greater, and since I abhor having to stop at the gas station for fuel every couple of days, in continued my practice.
I've filled up last week with a super full tank ( how? when pump stops pull nozzle out to about 2 inches from inlet, and slowly hand pump gas until fuel doesn't drain down the pipe any more)... so anyway, I filled this thing up with 24.3 gals and got 360miles out of it, for a whopping 14.8 mi/gal city.
The updates however are as follows:
1. I have not been driving like a grand mother, but rather like I'm 26, and the thing actually either improved, or yielded the exact same fuel economy. This is awesome because I can drive like I am normal, and still get the same economy, although still pretty bad in my opinion.
2. Contrary to earlier posts about detrimental fuel economy from an overfilled tank, overfilling up my tank did not cause noticeable adverse fuel economy, yet my range increased sweetly. If you think of this big brother guzzling down a gallon of gas every time you run an errand, it will likely gargle all the gas in the pipe by the time you get home.
My thoughts regarding later GX models getting 16+ mpg city:
Range:
Earlier models: ~14 x 24.3 = 360mi
Later models: ~16 x 24.3 = 388.8
Results: The newer models can drive ~28 miles more on the same fuel, so lets subtract those extra 28 miles from the newer 16mi/gal models to make them drive the same range as our earlier 14mpg GX's. This results in the newer models requiring 22.5 gals to drive the same distance that our earlier GX's drive on 24.3, so the difference is 1.8 gallons.
At fuel prices
07.11.2011, Orlando, FL
87o $3.47/gal x 24.3 gal = $84.30
93o $3.69/gal x 22.5 gal = $83.02
THUS, us with older GX's pay $1.3, (a dollar and 30 cents more) per tank to drive the same distance as those with the 16mpg newer GX's. In other words, the financial difference is negligible, The issue is just the plain fact that these cars should be more efficient. Period.
contrary to a post from a couple of days ago which warns about overfilling the tank, I figured that nothing had ever happened, yet my range was much greater, and since I abhor having to stop at the gas station for fuel every couple of days, in continued my practice.
I've filled up last week with a super full tank ( how? when pump stops pull nozzle out to about 2 inches from inlet, and slowly hand pump gas until fuel doesn't drain down the pipe any more)... so anyway, I filled this thing up with 24.3 gals and got 360miles out of it, for a whopping 14.8 mi/gal city.
The updates however are as follows:
1. I have not been driving like a grand mother, but rather like I'm 26, and the thing actually either improved, or yielded the exact same fuel economy. This is awesome because I can drive like I am normal, and still get the same economy, although still pretty bad in my opinion.
2. Contrary to earlier posts about detrimental fuel economy from an overfilled tank, overfilling up my tank did not cause noticeable adverse fuel economy, yet my range increased sweetly. If you think of this big brother guzzling down a gallon of gas every time you run an errand, it will likely gargle all the gas in the pipe by the time you get home.
My thoughts regarding later GX models getting 16+ mpg city:
Range:
Earlier models: ~14 x 24.3 = 360mi
Later models: ~16 x 24.3 = 388.8
Results: The newer models can drive ~28 miles more on the same fuel, so lets subtract those extra 28 miles from the newer 16mi/gal models to make them drive the same range as our earlier 14mpg GX's. This results in the newer models requiring 22.5 gals to drive the same distance that our earlier GX's drive on 24.3, so the difference is 1.8 gallons.
At fuel prices
07.11.2011, Orlando, FL
87o $3.47/gal x 24.3 gal = $84.30
93o $3.69/gal x 22.5 gal = $83.02
THUS, us with older GX's pay $1.3, (a dollar and 30 cents more) per tank to drive the same distance as those with the 16mpg newer GX's. In other words, the financial difference is negligible, The issue is just the plain fact that these cars should be more efficient. Period.
07-11-11, 08:26 AM
#51
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^^^ wow do you keep extra gas in the car in case you run out.
The thing that bothers me is the range. My gas light comes on at around 270miles which means I have to fill up at least twice a week. I don't expect much in gas mileage on the GX but my yukon would go over 300 miles easily, with a bigger tank of course.
The thing that bothers me is the range. My gas light comes on at around 270miles which means I have to fill up at least twice a week. I don't expect much in gas mileage on the GX but my yukon would go over 300 miles easily, with a bigger tank of course.
12-14-11, 04:39 PM
#53
Driver School Candidate
To have clean running engines Lexus changed the recommendation and made the premium fuel the requirement. It has to do with meeting the ULEV II certification requirements.
Here is the difference between LEV and ULEV II
"ULEV II: Ultra-Low-Emission Vehicle, a mid-level Phase II LEV standard. Hydrocarbon and carbon monoxide emissions levels are nearly 50% lower than those of a LEV II-certified vehicle."
Here is the difference between LEV and ULEV II
"ULEV II: Ultra-Low-Emission Vehicle, a mid-level Phase II LEV standard. Hydrocarbon and carbon monoxide emissions levels are nearly 50% lower than those of a LEV II-certified vehicle."
The only engines that truly need a higher octane fuel are high compression, high-performance....that's it. As for the GX.....not even close. Again, this is the same engine as the 4-runner, which says nothing in the manual about using high octane fuel.
I'm certainly not poor.....and can certainly afford to pay for premium fuel--I'm just not a fool nor a tree hugger. The premium fuel scam is just a ploy to get us people with money to pay for more silly government pipe dreams that just don't work!
12-14-11, 04:44 PM
#54
Don't believe the Lexus hype.....This is the same exact engine as the 4-runner and tundra. the only reason the manual says to use high octane fuel is for cleaner emissions, and has nothing to do with performance, maintenance, carbon build up, etc. If being "green" is worth the extra $1.00 per gallon to you, then go for it. As for me, I'll stick with 87 non-ethanol. 10% ethanol in gas is terrible for internal engine parts, reduces your fuel mileage, and causes moisture in your fuel to congeal into gobs of white goo that will clog your fuel system in a heartbeat. Leave a tank full of ethanol-added fuel in your car for a few weeks and it will run like crap. You can fix it by adding in a bottle of sta-bil most of the time.
The only engines that truly need a higher octane fuel are high compression, high-performance....that's it. As for the GX.....not even close. Again, this is the same engine as the 4-runner, which says nothing in the manual about using high octane fuel.
I'm certainly not poor.....and can certainly afford to pay for premium fuel--I'm just not a fool nor a tree hugger. The premium fuel scam is just a ploy to get us people with money to pay for more silly government pipe dreams that just don't work!
The only engines that truly need a higher octane fuel are high compression, high-performance....that's it. As for the GX.....not even close. Again, this is the same engine as the 4-runner, which says nothing in the manual about using high octane fuel.
I'm certainly not poor.....and can certainly afford to pay for premium fuel--I'm just not a fool nor a tree hugger. The premium fuel scam is just a ploy to get us people with money to pay for more silly government pipe dreams that just don't work!
05-03-12, 08:55 AM
#55
Lexus Champion
I'm getting the same thing maybe a little less. The funny thing is when I first got it at 40k miles I was getting 16 mpg from my usual driving all the way til about 110k miles. I let my brother use it for about 20k miles (but only about 3 months() when I got it back I got 14.1, 14.2 14.1 mpg when I didn't need a/c then 13.1, 13.3, when I used a/c (hand calculated) My on board says 16 mpg. I used to get a little over 300 miles to the tank easily. Now the light comes on at about 250-260.
There's a few things I'm going do and report back to see if there are any improvements
1. Check brakes/calipers
2. change air filter
3. change all the drivetrain fluids.
4. change the spark plugs.
There's a few things I'm going do and report back to see if there are any improvements
1. Check brakes/calipers
2. change air filter
3. change all the drivetrain fluids.
4. change the spark plugs.
Did you see any improvement?
I have a '05 GX and I do nothing but city driving and Im getting about 240-250 miles per tank = 11mpg. I had a lifted '06 Tundra DC with 33" M/T tires and I got just as good gas mileage as the GX and I drove it like I stole it. Im constantly babying the GX, trying to keep the RPMs under 3K and I cant seem to improve the gas mileage? Both the Tundra and the GX have the same V8 and weight almost the same too: (GX: 4,871lbs. / Tundra DC: 4,780lbs.).
All of the fluids, other than the trans, has been changed. I tried removing the ground wire from the battery thinking the computer will relearn my driving habits but it didnt help. I recently changed the air filter and cleaned the MAF sensor. I dont have any stuck / dragging calipers. My tire pressure is 36lbs., I might try to bump it up 1-2lbs. to see if it helps. The only thing left to do is change the spark plugs.
I wasnt expecting great gas mileage but 11mpg is pretty sad.
05-03-12, 10:58 AM
#56
Did you see any improvement?
I have a '05 GX and I do nothing but city driving and Im getting about 240-250 miles per tank = 11mpg. I had a lifted '06 Tundra DC with 33" M/T tires and I got just as good gas mileage as the GX and I drove it like I stole it. Im constantly babying the GX, trying to keep the RPMs under 3K and I cant seem to improve the gas mileage? Both the Tundra and the GX have the same V8 and weight almost the same too: (GX: 4,871lbs. / Tundra DC: 4,780lbs.).
All of the fluids, other than the trans, has been changed. I tried removing the ground wire from the battery thinking the computer will relearn my driving habits but it didnt help. I recently changed the air filter and cleaned the MAF sensor. I dont have any stuck / dragging calipers. My tire pressure is 36lbs., I might try to bump it up 1-2lbs. to see if it helps. The only thing left to do is change the spark plugs.
I wasnt expecting great gas mileage but 11mpg is pretty sad.
I have a '05 GX and I do nothing but city driving and Im getting about 240-250 miles per tank = 11mpg. I had a lifted '06 Tundra DC with 33" M/T tires and I got just as good gas mileage as the GX and I drove it like I stole it. Im constantly babying the GX, trying to keep the RPMs under 3K and I cant seem to improve the gas mileage? Both the Tundra and the GX have the same V8 and weight almost the same too: (GX: 4,871lbs. / Tundra DC: 4,780lbs.).
All of the fluids, other than the trans, has been changed. I tried removing the ground wire from the battery thinking the computer will relearn my driving habits but it didnt help. I recently changed the air filter and cleaned the MAF sensor. I dont have any stuck / dragging calipers. My tire pressure is 36lbs., I might try to bump it up 1-2lbs. to see if it helps. The only thing left to do is change the spark plugs.
I wasnt expecting great gas mileage but 11mpg is pretty sad.
To be accurate, you have to fill up, but dont keep squeezing after it cuts off. Then reset your "tripometer". During the next fill up, do the same thing and divide the mileage on the tripometer by the number of gallons.
If you're already doing that and it's coming out to 11mpg, something has to be wrong. Or you only drive uphill everywhere you go.
05-03-12, 11:38 AM
#58
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Did you see any improvement?
I have a '05 GX and I do nothing but city driving and Im getting about 240-250 miles per tank = 11mpg. I had a lifted '06 Tundra DC with 33" M/T tires and I got just as good gas mileage as the GX and I drove it like I stole it. Im constantly babying the GX, trying to keep the RPMs under 3K and I cant seem to improve the gas mileage? Both the Tundra and the GX have the same V8 and weight almost the same too: (GX: 4,871lbs. / Tundra DC: 4,780lbs.).
All of the fluids, other than the trans, has been changed. I tried removing the ground wire from the battery thinking the computer will relearn my driving habits but it didnt help. I recently changed the air filter and cleaned the MAF sensor. I dont have any stuck / dragging calipers. My tire pressure is 36lbs., I might try to bump it up 1-2lbs. to see if it helps. The only thing left to do is change the spark plugs.
I wasnt expecting great gas mileage but 11mpg is pretty sad.
I have a '05 GX and I do nothing but city driving and Im getting about 240-250 miles per tank = 11mpg. I had a lifted '06 Tundra DC with 33" M/T tires and I got just as good gas mileage as the GX and I drove it like I stole it. Im constantly babying the GX, trying to keep the RPMs under 3K and I cant seem to improve the gas mileage? Both the Tundra and the GX have the same V8 and weight almost the same too: (GX: 4,871lbs. / Tundra DC: 4,780lbs.).
All of the fluids, other than the trans, has been changed. I tried removing the ground wire from the battery thinking the computer will relearn my driving habits but it didnt help. I recently changed the air filter and cleaned the MAF sensor. I dont have any stuck / dragging calipers. My tire pressure is 36lbs., I might try to bump it up 1-2lbs. to see if it helps. The only thing left to do is change the spark plugs.
I wasnt expecting great gas mileage but 11mpg is pretty sad.
I did put regular in it when we drove from Spokane, WA to Long Beach, WA (about a 450 mile trip) and noticed I lost an equal amount of miles per tank as I would've lost in cash-in-my-pocket by buying Premo in the first place. Can't really say power/performance was really affected, but I'm usually lead-footin' it most of the way anyways. Therefore-hest, I still use premium.
I'm no tree hugger by any means (my 08 Tundra w/ the 5.7 getting around 15 mpg (summer) and 13 mpg (winter) can prove that on it's own), but I'm glad premium is cleaner burning and gives me similar gas mileage, too.
05-04-12, 03:59 AM
#60
RCsGX,, It hit 90 degrees plus in Ohio (rare), the last day or so. AC on and pumping. Didn't do any accurate testing, but the air conditioner always seems to cut into the mileage (1 to 2 mpg). My sister lives in Houson, you must have your air conditioning on all the time.