Help!!! Terrible gas mileage!!

Five full tanks and 2081 miles later.
My last tank was less MPG due to the drive on beach and AC use.

 

14.22MPG.

 

+9 mpg=23.22 mpgs(on my best day) is what I get with a stock 2.7l auto 4x4

 

I get about 13-14mpg... to be expected though with lift and 35s.

 

My last tank after 2 cans of SeaFoam run through the tank is 18.14. My normal MPG with my setup is 17.50.

 

I'm at 20 right now

 

You also have the 3.5 liter gen 3, this is about the 4.0 liter in the gen 2

 

I suggest doing a Seafoam treatment using the kind where you spray it through the intake while someone revs the engine at 2000 rpm until the can is empty. I'm still on the first tank after doing it (130k miles on my 2008), but there's definitely a rise in MPG so far

 

Thank you thank you thank you. This is my point exactly.

 

I haven't had time to read the whole thread, but have you considered the timing chain or other timing components yet? This is very common on modern vehicles. I have experienced this numerous times in various trucks. Particularly on start-up you will hear a heavy, labored rattle - often interpreted as a rough idle. Sometimes it can manifest as a "lean" condition and the computers compensate by increasing the idle speed. Normal should be around 750-1000rpms. If your truck is over 150k miles, its not a bad idea to consider. On Tacos, its not terribly difficult, but will require tools and time.

Obviously, try seafoam, cleaning your fuel injectors, cleaning your throttle body (do this when you do the seafoam treatment), replacing your maf sensors, and laying off the peddle first. If still no improvement, you have worn engine components, the timing is usually the first to go. Oh, one more thing - switch to all synthetic and still change it every 3-4K.

If you have access to a obdII code reader plug it in and send us your numbers. We will be able to offer a lot more than a slew of off-the-cuff quick fixes.

Good luck.

 

My mpg recently jumped by 3 when I changed my brake calipers out along with tie rod ends and an alignment. I’m thinking sticky caliper was my deal. Been fighting low mpg’s for years. Went up from 13 1/2 to about 16 1/2.

 

Congrats on figuring it out. Also, thank you for posting the resolution.

 

Not to be rude, but I'd sacrifice 9mpg in a heartbeat to go from a 2.7 to my 4.0 I love this engine. And if I get 12-14mpg on average for the rest of the trucks life, I'll take it.

Another reason I love the 4.0:
www.tacomaworld.com/threads/how-are-you-supposed-to-drive-uphill.558792/
And this:
https://www.tacomaworld.com/threads/lack-of-power.558765/

But hey, at least y’all get great mpgs right!?

This was more a test to see if grandma driving would make a huge difference, which I've decided it doesn't.

 

Whatever suits. Even the 4.0L in my last truck was no rocket and certainly not worth the extra in fuel it took. It's a work truck, supposed to help me make money, not waste it.

 

well said, and if gas mileage and fuel effeciency is a priority than buying a v6 and adding big tires, lift kits, super chargers, unsprung weight will drag those MPG numbers down to where they are complaining about getting. I just common sense that you wont be getting awesome MPGs numbers when u are shooting yourself in the foot buying a larger engine truck and then modifying a truck to look cool and expecting 20+ plus mpgs like the new car sticker says..

 

Had to take a short trip...

 

Get that turd gen outta here.

 

So since my last update, where I got 14.22MPG driving like a grandma, I have changed my oil, and tranny fluid. That's it. I switched from Mobil 1 5w-30 full syn, to Pennzoil platinum 5w-30 full syn. The tranny oil changed from factory to Red Line MT-90 full syn. This last tank I got..... wait for it.....

15.5MPG

And I was driving like normal. Nothing special, not trying to get good mpgs. I even towed a trailer for 2 days while helping a buddy move. Perhaps the oil had some effect, perhaps not. We will see if I can keep this trend going.

 

Last weekend I changed my two downstream O2 sensors and gained 2.5 MPG‘S.....