Hi, Im in Aussie Land and have myself a 91 4runner, Ive only had not long and did a rebuild of the engine 3vze before i got the car registered.
My problem is i live 100ks away from my work and have a fair wack of freeway to travel but im putting in $50 of fuel (31L) and only getting 150k from it.
it works out at 100miles to 8.45gal that equates to around 11mpg.

So what ive done is....

Full engine rebuild, New Dissy cap, New rotor, new air filter, new spark plugs, new leads. and dont a proper engine tune up. I do have another fuel filter here to replace but i cant see that changing much, Also the engine had no error codes apart from 4-3 whats starting system (not sure what that means but nothing to do with mpg im guessing)

If any one else has a suggestion i would appreciate it. thanks

 

hey man, welcome. thought you should know the 3vze is not a very fuel efficient motor. if possible, id reccomend buying a 3.4 and swapping it in, and selling the rebuilt 3vze to see if you can get anything back for it. the 3.4 is a strong motor, and it gets good mileage too. what you could do though is retard the timing a little bit, ive heard of that for fuel economy. you would not have a lot of power, but you would be getting better gas mileage. hope it helps.

 

what is your Tire pressure at?

 

A faulty O2 sensor will make your MPG go down the crapper to.

 

tire pressures up to where they should be, fuel filter, valve adjustments, thinnest oil rated for your ambient temps and driving habits, TPS and AFM checks, verify the cold start system isn't malfunctioning, rear brakes not dragging.
a whole laundry list of things that can help with fuel economy.
and you'd be surprised what a clogged fuel filter can do- can make the engine sluggish causing you to press the skinny pedal harder.

 

^ x2... def check o2, and tire pressure... you wouldnt think it, but tire pressure makes a huge difference... I changed mine from 30psi to 45psi, and got an extra 4+ mpg. 11 mpg does sound quite low for a 3vze... are you running an auto, or 5spd? typically 5spd's get way better mpg's. I have both a 5spd, and an auto, my 5spd gets between 20-25mpg's depending on the type of driving. my auto gets between 12-14 lately...but thats all intown driving, and it has a code 52.
also check air filter, pcv valve, and get that fuel filter changed!!

 

i ran my super swampers at about 25lbs most of the time..(i used to) on my 1980 toyota 4x4 with the 20R and 4spd..i got around 12 on the highway...even worse in town...i pumped em up to 45...and i got about 18..did a tune up.and now im gettin close to 20...same thing on my '86 with the same super swampers..only im gettin 22-24..lol

 

How big are your tires? If you've got huge tires, two things will happen to kill your mileage. One, you big tires rotate farther per revolution- thus you will perceive lower mileage. Second, you will be undergeared- then engine struggle and you loose economy and power.

 

I can get 18mpg with my truck, big wide tires, lift etc.

Check:

o2 sensor
TPS adjustment

Do:

pump tires to 35-40psi
stay under 60mph (wind resistance)
Try to draft big rigs (it helps, even at 100ft)