Fuel filter

Location of fuel filter 2018 tacoma 2.7 liter my gas mileage started going downhill just all of the sudden went from 19-22 mpg to 13-15mpg. Air filter is new , spark plugs newish fresh oil and the maf sensor is clean

 

I'm not a mechanic, but my first thought when seeing worse gas mileage wouldn't be a fuel filter if the truck is otherwise driving normally. If it's not getting enough fuel you'd know it.

I'd keep going down your list of likely suspects. Maybe the fuel/air sensor in front of the cat and/or the O2 sensor behind the cat?

I'd also recheck any work done recently. Any vacuum or sensor lines not reattached?

 

Did you add weight in the areas of bumpers, tires, shell, roof top tent, etc?

 

When did you last replace the air filter, spark plugs? Did you change tire size?

BTW there isn't a serviceable fuel filter. The only filter is the strainer sock on the bottom of the pump.

 

If you plug in an OBD2 scan tool, what are the short term (ST) and long term (LT) fuel trim numbers?

What spark plug P/N did you use?

Any cracked or loose vacuum hoses?

Any leaks in the intake pipe?

How long ago were your driveline fluids replaced and what did you use?

As others said, a fuel line restriction wouldn't cause the truck to use more fuel.

 

How many tanks of fuel have you run through the truck since your MPG declined? I wouldn't take any harsh measures if the sample size is small.

 

We need more info. Gas mileage is highly dependent on the context. Hiway, city towing, idling, wind, slope, elevation, tires, and surface are a few of the many factors.

 

Heck a road trip in to a headwind will cost you 2-3 MPGs.

 

I believe external gas filters were 2004 maybe. A stupid redesign by Toyota engineers

 

Thanks guys for the quick response. I drive pretty much the same route every day. I just replaced all my fluids motor oil , transmission,differential, brake fluid and power steering fluid. I also changed transmission filter and gasket. I used all OEM fluids . What weird about it it just happened like over night one day im getting 19-22mpg next day getting 13-15 mpg . I normally wouldn't trip on gas mileage fluctuating but that much over night??

 

disconnect the battery for 5 mins then it will be better

 

Already disconnected battery to reset computer didn't make a difference

 

“What weird about it it just happened like over night one day im getting 19-22mpg next day getting 13-15 mpg“

Changes overnight? How many miles was this test run?
I’d verify over several tanks, for an accurate test.

 

Im gonna do that next but i just dont get how i could have such a drastic change over night truck has 75 thousand miles on it and has never been below 15 mpg maybe 14 mpg but thats only when i drive it hard. Soon as i stop driving it hard it goes right backup to 17-19 mpg now it just stay at 13 maybe 13.9 mpg like i said its never done this and nothing has been added to the truck its stock

 

I would bet a dollar to a donut you have a brake at one corner that is not properly bled and is constantly "braking".

Get an Infrared Thermometer like shown below. Does not have to be a Fluke quality, Harbor Freight is fine.


Scan the temps of your brake rotors (drums) the next time you drive. I bet you have one wheel that is 500F hotter than the other three and causing some serious drag. Thus killing your fuel economy.

Doesn't take much to decrease the fuel ecconomy on a small 4 cyl engine in terms of parasitic drag.

 

Maybe a sensor is failing but it isn't throwing any codes i think i will post the fuel trim numbers maybe that will help someone help me figure this out again thanks everyone for chiming in its greatly appreciated im a new member so forgive me if im going about this the wrong way still figuring this site out

 

Yes, post up your Fuel Trim numbers *and* and DTCs (dianostic trouble codes).

If your fuel trims are +/-5% and you have no DTCs, then you have a SERIOUS friction problem somewhere.

 

Thanks Big carbon footprint i will try that i was thinking about that possibility but i would think the truck would pull to one-side while brakeing

 

Not to double post back-to-back, but there is a comically simple way to test your brakes for excessive friction.

Jack each corner up. You should EASILY be able to rotate each wheel by hand with ease. Transmission will need to be in neutral to check rear wheels, obviously, which has nothing to do with the brakes.

Do this.

 

You shouldn't put much weight on the fuel mileage reported on one short trip. Just keep driving the truck and check it again. Also stop worrying about your fluids. Unless you accidentally filled the engine with 90W gear oil and it's -20F outside, it's not going to affect the gas mileage that much.