Poor Mileage

Ok I'll try high grade fuel with better/ more additives. The tires that were on the truck when purchased were slightly bigger and I got better mileage with them. To start, I will do the first tune up and use better fuel. Thanks for all the input

 

Try cleaning the MAF sensor and throttle body while your doing your plugs, I did that along with my plugs and jump up from 15 to 18 mpg. If the sensor is dirty and not reading right it will throw off the air/fuel ratio.
I honestly wouldn't be putting higher grade fuel into your tank unless its tuned for it. The marginal (if any) mpg gains you'll be getting will be offset by the higher price fuel. Plus like I said earlier, unless your truck is tuned for a higher octane, it's not going to help your cause, the computer will still think the lower octane is being used and wont adjust the air/fuel ratio. Only advantage for using higher octane is there is less ethanol that can eat away at your internals.

 

Typically youre exactly right about the different octanes. Most vehicles dont do any better on higher octane other than what the manufacturer tells you to use. These trucks can take advantage of it though, depending. Older models were actually recommended by toyota to use higher octane because of the high compression. Only the more recent year tacomas changed to using lower octane. In the owners manual it states that higher horsepower can be achieved with higher octane fuel. This is only because the sensors detect the type of fuel and adjust the timing of the motor, which can yield better power.

 

Give your throttle body and MAF sensor a good cleaning.

 

I Stand corrected. Just traded my ram 1500 for this taco a couple weeks ago, haven't read through the manual yet, thanks for informing me.
Still have to imagine the cost savings in performance would be marginal if you factor in the higher price per gallon. might have to do some experiments and see

 

For fuel, use Redline S1 fuel system cleaner. Highly concetrated and highly recommended by the SAE.

Do not use the seafoam through the intake. Lots of room for error, and it is an abrasive. Abrasives don't mix well with engines. It will clean it though. It certainly will.

 

My 2013 V6 Crew Cab PreRunner was averaging 21.7 combined up through 50k miles (city/hwy), according to my UltragGauge (which I think is a little generous, but a good way to compare apples with apples). After going to 265 Toyo Open Country II AT tires, that dropped to about 20.6 (most likely due to higher rolling resistance and weight increase), which was not unexpected.

Recently the average MPG has been slowly dropping - it's at 19.9 now, and no other changes have been made to the truck or my driving style (mostly expressway). Last changed the plugs at 30k. Using Mobil1 full synth, with Puralator Boss oil filter. The air filter has been a K&N unit from the beginning, and I clean it every 10k miles. It's probably due to be cleaned & oiled again, and I am definitely due for plugs (will go with Irridium, since they came with the truck). Been burning regular pump gas from day one.

Does anyone have any thoughts about the possibility of the O2 sensor(or sensors) needing attention? I know that will affect the mix (and mileage). Cleaning the MAS also seems like a good idea, so I will tackle that when I do the plugs (the left bank are a pain in the ass to get to).

 

I like seafood...

 

CURSES! Autocomplete strikes again!

 

If you don't like changing plugs often, get Iridium plugs; they will last 70-100K miles. I have NGK Iridium IX

$47 LFR6AIX-11 -6 PCSNEW

LFR6AIX-11 plugs. About to hit 90K but they do need changing as I'm beginning to feel slight hesitation on acceleration. Idles fine and MPG remains 15-17, as it has when new. I have the largest & heaviest Taco available with heavy mud terrain tires and a 2-inch lift.

 

I had an 07 FJ before I traded for the Tacoma. When the FJ had about 30-40,000 I noticed a dip in my mileage. Through my scan gauge I noticed my temp wasn't breaking 160 degrees. My thermostat was not closing which caused the ecu to constantly think it was in warm up mode and was running rich. I had a lot of black soot on my tail pipe and body. Might be something you investigate.

 

You said, "after going to a 265". What was the other number? As in was it also larger that the previous tire's second number( after the "/").

What are the tire specs of your older tires?

What is your tire pressure currently?


Tire pressure drops are the most significant factor for decreased MPG's. Secondly, are tires larger than stock, without a corrected speedo.

New changes create a new baseline for what your MPG will be. I.E. adding a lot of weight to the vehicle, or components which create a lot of wind drag, increasing the vehicle's coefficient of friction. Which can also be had from underinflated tires and/or wider tires.

 

Run it harder. Self modded coolant upgrade.

 

I get 20.5 with BFG KOs that weigh 49 lbs. This is hwy @ 70 mph average. I do not do much city driving at all. Do not think premium gas or air filter will change it much but plugs will.

 

My 07 DCSB 4x4 is driven 50/50 city highway and I averaged 19mpg running 265/70/17s and recently switched to 265/65/17s and now average 21.2. No other changes were made other than tire size and brand.

I can also add that the dealer left my airbox disconnected during a recall and mileage dropped to 18.9mpg.

 

Sorry. The original Dunlop street tires were P245/70/16. The Toyo's are P265/70/16 (essentially identical height/circumference). I run 32 PSI in them, as I did with the others (and monitor them fairly regularly). The Dunlops lasted to 55k miles, at which point I had the Toyo A/T's installed.

My “normal' combined mileage (without babying for best fuel efficiency-see below) averaged 21.7MPG on the Dunlops (according to the UltraGauge). With the Toyo's that dropped almost immediately to a solid 20.5, and stayed there until recently. That was expected, due to the increased rolling resistance caused by the more aggressive tread pattern and softer rubber of the A/T's, added weight, and possibly a minute increase in wind resistance.

I rotate the tires every 5k miles (yay, impact wrench!), and inspect for uneven or unusual wear patterns – so far they still look pretty good, with 20,000 miles on them – the siping is still pretty sharp, and plenty of tread is still left. The wheels all rotate freely, with the truck on jackstands.

The truck has a little over 75k miles on it at this point. About a month ago, the average MPG started dropping from 20.5, and is now at 19.9 (and still decreasing, presumably).

I just ordered a set of irridium plugs (all NGK... sorry, Denso), and MAS and Throttle Body cleaners from CRC. If that doesn't help, I will start looking at the O2 sensors.

p.s. -
For a short period, with the original tires installed, I drove as efficiently as possible, and at one point had the average MPG up to 22.5, but that involved backing off the throttle on uphills (overpasses, here in S. Florida), VERY unaggressive acceleration, and staying at lower speeds on the highway (65 or less). This got very tiresome after awhile, and I decided it wasn't worth the minimal improvement, for the stress and frustration of being a moving roadblock.

 

I get up to 320 or higher before I start to hover around "E" close enough to make me uncomfortable. I'm sure I could make it to 380 before I ran out, I always seem to only pump 17 out of the 21 gallon tank.

Miles

 

All these mileage figures are meaningless for comparison without details. (Engine, trans, 2wd or 4wd, tire size and type and percent of city/highway driving) Without that information it's just what you get and no comparisons can be made.

 

The 265/70 R16 is a tad over an inch taller in diameter than the 245/70 R16.

30.6" to 29.5". That will skew your mileage, showing less driven than actual, which will also lower your perceived MPG.

 

I run 91 octane due to my supercharger, and I always add a bottle of octane booster whenever I go off-roading. Before my last outing, I had half a tank of 91 in my truck with octane booster, I went to fill up and added another booster to it. I've been getting FANTASTIC gas milage on this tank now, better than I normally get with mixed city/highway and the first quarter tank was all off-road, mostly in 4lo. I can only assume that added octane actually helped my mileage...not sure if this is recommended on N/A applications but thought I'd throw it out there. The cost of the boosters probably off-sets and fuel savings anyway.