I have a 86 runner with auto and 22re with 31s. ive done tune up with Toyota parts and o2 sensor. im still only getting around 15mpg mainly hiway driving. the check engine light is on wondering if that has something to do with it.

 

The CEL may help but not much.

15mpg isn't too bad for a vehicle with the aerodynamics of a parachute.

Best things you can do to help is to take any extra weight out of truck and keep the tires inflated to proper pressure.

 

Find the code first.

 

Ive been fighting with mine since I got it. I have 32's auto 22re.

Ive just replaced my tps and re set my timming. Have alot more power and running beter

I have been averaging 8/9 mpg
I just fixed the tps half Way through the tank and did see my best tank so far getting 10.75

Im dreamin of getting 15mpg in the city and 22 on the highway

 

I know that a 5 speed with 4.10s' and 31's can do that, and even a little better.

 

i had a buddy of mine that had 3 codes on his 88 pickup i ran thru and fixed it all it ran a hole lot better and did a little better on gas i think it got about 16 or 17 on 33s

 

Are you guys adjusting mileage driven for larger tires?...

 

yes. i have a 20r and i get 8 city and 10 highway with 4.10s. it all dipends on how well the motor runs and how you drive with a 5 speed.

 

My JunkRunner has actually travelled almost 108 miles when the odometer shows 100 miles run. I take this into account when calculating MPGs'.
This is strange odometer behaviour, because the speedo itself reads near 10 MPH fast.
Really doing 65 when the speedo says 75.
Speedo is wrong on one side of true and the odometer is wrong on the other side of true.
All good though, because I know what the actual measures are.

 

70ish miles on this new tank of gas. And still above 3/4's of a tank. Looks like a new tps and a ignition timing adjust has done the trick.

I know my speedo is off cause of the tires and assumed my odometer was off as well. But it being off 5-7mph shouldn't cause a 8-10mpg short.
Ill post again when I refill next week or so

 

Clock the odometer reading against the highway mileposts to check for accuracy.
10 miles will do it.
You can't necessarily draw any conclusions about what the odometer measures by how much the speedo is off.
They can have different errors, as my case shows.

 

Definitely recommend adjusting tps

 

I fueled JunkRunner today and did a fuel mileage calculation.
Total miles: 405
Total fuel consumed: 19.09
MPG= 21.21
A little lower than usual, but this mileage run included quite a bit of desert road and low range travel.