Horrible fuel mileage

Cutler133

New member
I just bought a 95 4runner and love it. The only thing I don't love is that I get 160 miles out if a tank of gas. I've replaced the spark plugs and am going to replace the fuel filter. My question is I was told I need to change the o2 sensor how many are there. I was able to find only one but the guy at o'riley told me there are two as far as I know this isn't a Cali truck. I don't have anything crazy on it as far as lifts or tires. If it's not the o2 sensor what else could it be. It has 190k on it.
 
Register to hide this ad
I just bought a 95 4runner and love it. The only thing I don't love is that I get 160 miles out if a tank of gas. I've replaced the spark plugs and am going to replace the fuel filter. My question is I was told I need to change the o2 sensor how many are there. I was able to find only one but the guy at o'riley told me there are two as far as I know this isn't a Cali truck. I don't have anything crazy on it as far as lifts or tires. If it's not the o2 sensor what else could it be. It has 190k on it.

That's not really bad gas mileage it's probably about 13-14 mpg which is average. Use the search and you will find what you need
 
Yeah honestly that's what I used to get out of my 2nd gen as well. It had 170k miles and I got around 175-200 miles on a tank or 14 mpg, and my current 3rd gen (275k) gets 180-220 miles before I fill up which means around 15-16 mpg ish on average.

My 2nd gen was a 5 spd V6 4WD with 4.10 gears, stock tires size.
 
Last edited:
What size tires do you have? My '89 runner usually gets 16+.. and it's carburated. When I first got the truck it was VERY low on power and got shit mileage, partly due to the 31" tires, but later I realized the dope that owned it before me had oiled the paper filter in it. Now I have a new filter and 235/75's and can get 200 miles out of a tank no problem.
 
@o2 sensor question, there are two, a pre cat and post cat sensor. At least on my 94 it was that way.

Make sure you account for speedometer discrepancy with the larger tire size too. Either way though, larger tires will eat into your fuel mileage regardless. I just got rid of the 33's on mine and the mileage is noticeably better, (went from 13 to 17).
 
I've got 31's on it I believe it has the 17 gal tank on it

Either way that still means your probably getting At least 12. Which is common for these TRUCKS if you want gas mileage don't have a truck that's about all that I can say. I get about 15 city and 20-22 hwy. but my engine has 70k on it.
 
Either way that still means your probably getting At least 12. Which is common for these TRUCKS if you want gas mileage don't have a 3.0 that's about all that I can say.

Fix'd. Even the 4.7L 2uz V8 pulls much better mpg that the perennial favorite 3.0

Your driving style and situation has a lot to do with it. A 3.0 can probably pull 20mpg under very ideal conditions, but will pull 11mpg with rush hour traffic and a lead foot.
 
It's funny how as the 4runner evolved, the engines got bigger and the fuel economy went UP as well.

Running average of my 3.0 was 13.5 mpg
3.4 currently is around 16.
Now I have a 4.7 and I get close to 19.

Best I ever did on my 3.0 4x4 was 19.2 mpg, 55 mph cruise 100% of the time. Misc: My old 22r runner would average 18 mpg but rarely go over 20-21 on the freeway. It had 33's on it.
 
Last edited:
lots of variables to gas mileage. gearing/engine combo is one. driving style is another. tire pressure. weight of stuff in rig. etc.

my '87, running 30-inch snows @ 35 psi, with a 22re, has averaged 19.3 mpg since january 1st, going 4700 miles. the lowest "tank" avg was 17.1, and the best tank avg was 21.5. the most recent 4 tanks have averaged above 20.

anecdotally, toyota 6 cylinder gas engines, either inline or vees, don't seem to get particularly good fuel mileage. 4s and 8s seem to be better.
 
^^Only in trucks it seems to be true. Not sure why, but my old 3vz ES300 would do 25 mpg day in and day out, same with my Camry, but the 4 runner and pickup, 14-15 if I was lucky. I know that trucks are heavier and less aerodynamic, but that big of difference I would expect, especially since I never pushed them hard either.
 
My previous car was a manual 89 V6 Acura Legend, and it got around 22mpg I believe. A little better than my 4runner, but not earth shattering. And it was quicker, lighter, more aerodynamic, had street tires, and geared much differently.

I've had my manual 92 v6 4wd 4runner has gotten as good as 21mpg in the 10 years I've had it, and averaged maybe 19.5 when I was commuting and going through a tank a week (300-340 miles, from 7500' down to 6800', up to 8900' and down to 4500', and then back). But I was only over 55-60 mph for maybe 4 miles once the route hit the freeway. This is with BFG AT's, and not too much extra weight in the truck.

OTOH, this "tank" was winter blend, with lots of short trips when cold. We've added a few gallons here and there for a while, and are finally doing a fill-up today (gas is up to 50 cents more a gallon here than over the hill, and I try not to support that). And it turned out my tires were on the low side, and I just fixed one of the brakes that was touching just a little bit on part of the rotation. We'll likely be looking at 12mpg, vs the worst ever in the past 10 years has been 13mpg.

(we're above 20% of the atmosphere, and I'm thinking the computer uses a default set of values until warmed up, which would mean on all of those short cold drives around town it's fuel/air mixture is completely screwed up)

If doing worse than 12-13mpg, or if getting that low even when driving conservatively on longer drives without a bunch of extra weight, then look into it. Air filter. Brakes. Lubbed wheel bearings. In the FSM (page EM-81 in my '92 set) there are 22 troubleshooting things to look into for Poor fuel economy in the V6. If still having trouble, start ticking through them, starting with the most probable (#1).
 
i average about 14-14.5 mpg out of my 95 runner with an auto and 4.88 gears, it sits on 29's... maybe an air filter change, i don't know when it was done last to be honest. but i've noticed 13.5-14.5 is about the norm. also, i've heard if you change to manual hubs that could save some mpgs as well, i'm sure not much, but every mpg counts. good luck!
 

Members online

Forum statistics

Threads
278,311
Messages
3,554,082
Members
248,016
Latest member
Advally Service

Trending content

Back
Top