Drop in gas mileage?
#1
Drop in gas mileage?
Wanted to get some ideas as to what may be causing a recent drop in my overall gas mileage. I have not changed my basic driving habits ( no hard acceleration, jack rabbit starts etc). I can see no difference in overall operation or performance. There is no indication of an issue, no CEL indications nothing out of the ordinary, but my milage has gone from around 300-340 miles to a tank to around 225-240 a tank. Could one or both O2 sensors cause this? Any other things I should be looking at or checking for adjustment/replacement? Thanks for the inputs!
#6
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Depending on your regional EPA regs, this is the time of year (March 1 here) when refiners switch to Summer blend fuels that are reported (by me and others) to increase fuel consumption by about 10%.
That doesn't explain your 33% drop fully, but it's a start. I'd check the obvious first like tire pressures and air filter, then go to the harder, more expensive stuff like plugs. O2 sensor maybe, but wouldn't that throw a code?
That doesn't explain your 33% drop fully, but it's a start. I'd check the obvious first like tire pressures and air filter, then go to the harder, more expensive stuff like plugs. O2 sensor maybe, but wouldn't that throw a code?
#7
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I'm in the same boat- I'm attributing it to winter fuel+other cause. The Plugs and Wires are due- overdue- and I was hoping a MAF/throttle body cleaning would fix the low mileage when my day off+nice day arrives. I've been considering Seafoam too. (would have to do that BEFORE the plug/wire swap though...) I've been loathing the thoughts of an O2 sensor problem...
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#8
Maybe you suddenly got better at math? You don't mention what's a tank either. 15-16 gallon fill up?
Consistently getting 300-340 miles out of 15-16 gallons is kind of far fetched to begin with.
Consistently getting 300-340 miles out of 15-16 gallons is kind of far fetched to begin with.
#10
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It's a Washington State thing... Senate Bill 6508 (http://apps.leg.wa.gov/documents/bil.../6508-S.SL.pdf), all gas stations to have a 10% ethanol blend, but it can be as high as 20% (even though the pump is labled as 10%). Your gas station probably just switched over.
We can thank the corn lobby and the uneducated greeners who think that the blend is reducing emissions.
If you change your thread title to Washington State Drop In Gas Milage, I bet tons of people are experiencing the same thing (I know I am).
Write your state senator and representative (http://apps.leg.wa.gov/districtfinder/), I already have... there was a bill to provide at least one pump with non-ethanol gas (for marine and avaiton use - ethanol does bad things to fiberglass, and it's a safety issue in aircraft), but Washington state is a feel-good-go-green-say-wa state so the bill was swiftly killed.
We can thank the corn lobby and the uneducated greeners who think that the blend is reducing emissions.
If you change your thread title to Washington State Drop In Gas Milage, I bet tons of people are experiencing the same thing (I know I am).
Write your state senator and representative (http://apps.leg.wa.gov/districtfinder/), I already have... there was a bill to provide at least one pump with non-ethanol gas (for marine and avaiton use - ethanol does bad things to fiberglass, and it's a safety issue in aircraft), but Washington state is a feel-good-go-green-say-wa state so the bill was swiftly killed.
Last edited by skjos; 04-02-2009 at 10:59 AM.
#11
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i got 250 miles on a good tank. testing O2 sensor are very easy with a multimeter, find a service manual and get the specs based on your vehicle. i don't know if there's california emission or no on your year 4runner.
#12
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It's a Washington State thing... Senate Bill 6508, all gas stations to have a 10% ethanol blend, but it can be as high as 20% (even though the pump is labled as 10%). Your gas station probably just switched over.
We can thank the corn lobby and the uneducated greeners who think that the blend is reducing emissions.
If you change your thread title to Washington State Drop In Gas Milage, I bet tons of people are experiencing the same thing (I know I am).
Write you state senator and representative (http://apps.leg.wa.gov/districtfinder/), I already have... there was a Republican sponsered bill to provide at least one pump with non-ethanol gas, but Washington state is controled by the Democratic party so the bill was swiftly killed.
We can thank the corn lobby and the uneducated greeners who think that the blend is reducing emissions.
If you change your thread title to Washington State Drop In Gas Milage, I bet tons of people are experiencing the same thing (I know I am).
Write you state senator and representative (http://apps.leg.wa.gov/districtfinder/), I already have... there was a Republican sponsered bill to provide at least one pump with non-ethanol gas, but Washington state is controled by the Democratic party so the bill was swiftly killed.
#13
15 gallons, 300 miles is 20 mpg
15 gallons, 350 miles is 23.3 mpg
15 gallons, 225 miles is 15 mpg
15 gallons, 250 miles is 16.6 mpg
So how is this far fetched as you said to get 23 mpg?
On my trip to California just this past July, driving I-5 @58 miles per hour using cruise control, not romping it, power passing, running 70mph just because you can legally, I got anywhere from 21-24. Around town here at home, I normally get 18-20. I was consistantly going 300 miles on 15-15.3 gallons in town driving,(20.00-19.6078 mpg) so I did the math ... when I fill the tank, I fill the tank. I normally will not let the tank get too far below 1/4, don't like to see that little gas pump light come on.
#16
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Please post how the testing goes.
More on my ethanol tirade - Ethanol doesn't store well either (absorbs water), after it was in my motorcycle for 4-months I could no longer get my bike to idle. I went to the local airfield and filled it up with 100LL (100 octane, low-lead, NO ETHANOL) and it now idles like a dream.
More on my ethanol tirade - Ethanol doesn't store well either (absorbs water), after it was in my motorcycle for 4-months I could no longer get my bike to idle. I went to the local airfield and filled it up with 100LL (100 octane, low-lead, NO ETHANOL) and it now idles like a dream.
Last edited by skjos; 04-02-2009 at 11:07 AM.
#17
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california emission vehicles were sold nationwide, not just within california. why i ask? because on a ca spec 4Runner, the first bank1 sensor is an Air/Fuel ratio sensor, not an "Oxygen" senor, thou they look the same. one way to find out is to call a Toyota dealer service dept. foreman, give your VIN, they can pull it out of the computer.
#18
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I get the same question all of the time. First check your basic... air filter, tune up, and check the air in your tires. Then see if you can get a scan tool with the O2 sensor parameters and fuel trim (not sure if Toyota goes by FT numbers though). The O2 sensor should vary when in closed loop from 20mV up to 800mV on the pre converters.
#19
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I get the same question all of the time. First check your basic... air filter, tune up, and check the air in your tires. Then see if you can get a scan tool with the O2 sensor parameters and fuel trim (not sure if Toyota goes by FT numbers though). The O2 sensor should vary when in closed loop from 20mV up to 800mV on the pre converters.
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my mpg is down to and the check engine light was on and off for awhile and now its stuck on so while i was getting all my new parts for my tune up i got the check engine light checked and my o2 sensors are out... and i wasn't sure if on a 4runner if it mattered.. but now that i read this i think that i will fix em...
i had a 98 eclipse rs and my o2 sensors going out actually helped my gas mileage it went from 30mpg to 36mpg on the hwy...
but i guess its a totally different thing for my runner
i had a 98 eclipse rs and my o2 sensors going out actually helped my gas mileage it went from 30mpg to 36mpg on the hwy...
but i guess its a totally different thing for my runner