Bad gas mielage?

[Nunyabiz]

Nunyabiz,

What kind of spark plugs are you running?

I just replaced plugs that the previous owner had in it which were NGK Iridiums probably had 30,000 miles on them and they looked good still, all were burning good, none wet, all good color.
I replaced them with the double electrode NGK Laser Platinums.
Running very smooth.
Also replaced the wires with the NGK wire set.

Replaced the front 02 sensor.
Cleaned the MAF
Cleaned throttle body
Air Filter (K&N) is clean and lightly oiled though should probably be replaced because PO looks like he beat on it and dragged behind the truck.
Just replaced the water pump and all belts and thermostat
All fluids are 100% synthetic including ATF
Tires properly inflated

I have not unplugged the battery or yanked the fuse.

 

[Drcoffee]

the parts brands do make a difference. Which brand O2 sensor did you use? Bosch are terrible but whats available at parts stores.

You mention new Synthetic fluids and I assume differential as well. Have you checked your rear brakes and axle seals? If the axles are leaking into the brakes it would cause drag. I'm just giving you ideas since I don't know anything about your truck.

 

[Nunyabiz]

the parts brands do make a difference. Which brand O2 sensor did you use? Bosch are terrible but whats available at parts stores.

You mention new Synthetic fluids and I assume differential as well. Have you checked your rear brakes and axle seals? If the axles are leaking into the brakes it would cause drag. I'm just giving you ideas since I don't know anything about your truck.

Denso, I never buy anything but OEM parts.

No leaks, all axles are fine, all zerks greased.

I think some of my sad mileage problem is the fact that I live in a very hilly city, if I am not going downhill only means I am going uphill.
Probably cant go more than a mile anywhere in this town that is flat.

Thanks for the ideas though.

 

[Dous]

Denso, I never buy anything but OEM parts.

No leaks, all axles are fine, all zerks greased.

I think some of my sad mileage problem is the fact that I live in a very hilly city, if I am not going downhill only means I am going uphill.
Probably cant go more than a mile anywhere in this town that is flat.

Thanks for the ideas though.

I never thought Raleigh was that hilly. Maybe the Crabtree Valley area, but I dunno

 

[Nunyabiz]

I never thought Raleigh was that hilly. Maybe the Crabtree Valley area, but I dunno

That is exactly where I am, 2 miles north of Crabtree, everywhere I go its uphill downhill.

 

[CDN RUNNER]

Tando71
I have worked with toyota for 21 years. I have never known a runner to get more than 500kms a tank. I have seen it as low as 232kms a tank with 87 octane. These things are just fuel hogs but better than the 3.0L. If your getting 400kms to a tank that good.
Mine is an auto.
Check for dragging brakes and that's about it.
Good times....

 

[AZgeek]

If my conversion is correct (1 mile = 1.6 km) then I routinely get a little more than 510 km (300 miles) per tank on mostly city driving in my '01 Limited. Not great in comparison to my Prius but I am ok with it because it takes me places the Prius just can't go.

 

[rebelbowtie]

These are very reliable engines however at best the gas mileage is absolutely horrible for a 6 cylinder with less than 200hp and a fairly light SUV if compared to newer engines/SUVs today.

I mean really a freaking older Humvee with a 6.2L 400HP V8 that weighs about a TON more what our 4Runners do (6,600lbs) get only 1-2mpg less than I do.
and a H3 Hummer gets 14mpg city and 18hwy and weighs 6000lbs with 60 more HP than our 3.4L.

I get basically 12.8mpg average doing 95% city with a 10% ethanol gas.
I might get 19mpg hwy.

For a V6 3.4L today that would be atrocious gas mileage.

New 4Runners with a 4.0L get 17city 22hwy with 270hp.

Great trucks, great 4X4 ability, very reliable, looks great, just sucks on gas mileage no matter what you do unless you change the engine to a turbo diesel.
We should all be running around in fully electric 4Runners today burning zero gas and pulling up to work, grocery store, mall, virtually everywhere and plugging into a free charge station that runs on solar.
But sadly Oil Companies own Washington so until the very last drop of oil is drained or until people wise up that isn't going to happen in our life times.

no no no lol the 6.2 non turbo has 130-180hp(depending on LPG vs diesel) and 330lbs ft of torque. idk where you got the info they have 400hp

 

[Nunyabiz]

no no no lol the 6.2 non turbo has 130-180hp(depending on LPG vs diesel) and 330lbs ft of torque. idk where you got the info they have 400hp

I was referring to the " 6.2 L GM Vortec 6200" which is 393hp and not a diesel.
Was in the 2008 H2 Hummer

 

[rebelbowtie]

I was referring to the " 6.2 L GM Vortec 6200" which is 393hp and not a diesel.
Was in the 2008 H2 Hummer

you said "older Humvee" not the H2 Hummer

HMMWV aka "humvee"

H2 Hummer

 

[Nunyabiz]

you said "older Humvee" not the H2 Hummer

HMMWV aka "humvee"



H2 Hummer




Both the same to me, Hummer. Humvee, potato potahto

 

[Tango71]

Just an update guys. I did the seafoam treatment and wow what a difference. I now average 500-550km a tank on the highway and am pretty happy with that. I was able to achieve those numbers on on our trip to Alberta from Ontario going through the US. I wish we had the US gas prices here. It was a lot cheaper to fill up for sure as it equals to about $1.00CAD a liter. We pay $1.23/liter.

I would like to know if these 3rd gens had an EGR system and how much does the EGR system affect gas mileage? Would it be beneficial to remove it as there is no annual smog test where I live. Would doing this improve it even more?

 

[Young_gun]

is it weird that i get 13-14mpg in the city in my 2002 4wd on 33's? Truck looks awesome but gas bill, well not so much

 

[Maxil]

The only thing that stuck out to me was 2500 rpm's at 60mph? Mine will do that if I turn the O/D off, that just seems too obvious to be right hehe.

 

[Brian757]

First of all, lets convert kilos to miles for us Americans in here.
1 kilometer = 0.621371192 miles

Secondly, a factory 2000-2002 makes around 15 city, 17 highway.(Miles)
So, if you are making less than this, your probably on target because age does take tolls on vehicles. If your making significantly less than this, you have a problem.... Or your supercharged, lifted, locked, or don't know how to change fluids(Which I am sure youd know of these).

Also, I have 7 inches of lift, 33x12.50 tires, aftermarket intake/exhaust, racing headers/bored out pistons and i get around 280 miles for my 18 gallon tank. 280 divided by 18 = 15.56 MPG.

 

[KHoffRunner]

17.3 mpg mixed driving, moderately heavy on the gas. 2100-2200 rpm at 60mph.

I just went through my first tank if gas after an oil change this past weekend ans i got 19.4 mpg in my last tank with the same type of mixed driving.