New 02 Sensors = Mileage Increase

[MARLIN375]

And how exactly do you plan on removing the old ones?

Been spraying them with "moovit" for a couple of days.
I may have to take the front running board bracket off if the right side is a problem, it will make for better access (I also love bending the crap out of heat shields cause they do bend back)..........other than that I planed on just putting a 1/4 drive air ratchet w/deep socket on there and if the planets/moon/sun are lined up correctly they should come off.........Plan B, dissasemble entire vehicle leaving the two sensors for last.

 

[Bogman]

Plan B is beginning to sound attractive. Do you think a regular socket will work in there?

 

[MARLIN375]

Maybe a good quality one ( the cheap ones don't reset the pawl soon enough.......you need a short stroke in a tight spot )

 

[scottm]

My Gearwrenches came with socket adapters that fit in the gearwrench, with a socket drive square sticking out. That makes a super low-profile ratchet, maybe that'd help get you in there? My '97 must be set up differently, even with badly rusted nuts I could access them with a remover.

 

[94landcruiser]

Denso.com says they start in 1/95 I am not messing with it, I'll call Dan & get the right part the first time.


http://www.densoaftermarket.com/cat...o2sn&year=1995&make=TOYOTA&model=LAND+CRUISER

L6/4.5 GAS - FI N - D 234-4157 234-4206 FRONT N/A N/A From 1/95
--- L6/4.5 GAS - FI N - D 234-4153 234-4206 REAR N/A N/A From 1/95

 

[MARLIN375]

I am not messing with it, I'll call Dan & get the right part the first time.



If I lived in the "lower 48"......... that is exactly, what I would do. No question.

 

[landtank]

for what it's worth I lost some mileage when the new front sensor went it. But boy does the truck pull nice on hills. I'm down to 14 on the highway heavily modified.

 

[hobbes]

Bogman, IIRC the heat shields sit between the top of the O2 sensor and the bottom of the nuts in Raven's picture. You have to remove the nuts that hold on the sensors to get off the heat shields.

 

[HuletCruiser]

1997 TLC - O2 Sensor Wiring Diagram

Hello,

Frustrated with searching for the information I am looking for, I'm just going to have to ask.

Replacing Front O2 Sensor - 1997 TLC (CEL is on)

Denso OEM Universal Sensor
Wires are: White, Blue, Black, Black

1997 TLC
Wires are: Brown, Blue, Yellow/Red, Gray

???

What wire goes with what wire?

Give me a Miracle...

Thanks guys

Jason Hulet

 

[landtank]

everyone pretty much just installs the OEM stuff and hasn't dealt with this.

You want a miracle, return that sensor and contact CruiserDan at American Toyota.

 

[livinoffroad]

I guess I'm an idiot, but I could not figure out their site. I dutifully filled in the fields for year, model, make, etc and got...nothing. Hit the 'Find It!' button and got....nothing. Hit the NGK link hoping it would take me to some products and got...nothing - just a generic comment about how great NGK is. At this point I'd maxed out my personal time limit in figuring out a new site and was done with it.

DougM

I'm no genius, but I got lucky when, after I entered vehicle type etc., I used the drop down menu under "Product Search" and went to "O2 sensors". It lists both types, NGK and Denso. If a person wanted to save a few bucks, he could slip heat shrink tubing on, then solder the 4 wires, then shrink the tubing around the joint for a weather proof connection?

 

[Cruisin'Carolina]

Holy crap my head hurts after reading this whole thing!

Looks like I'm going in. Been playing phone tag w/ Dan for a couple of days, but I'm in no hurry. I have noticed a difference in mileage but don't have exact numbers.

I'll try to get mpg figures over the next couple of days, looks like next weekend not this will be the day. Great stuff, I love going into a project knowing the pitfalls. I have 110K now, so I guess I'll do both.

I threw a 2/8 code on my 94 a couple of weeks back, read it, reset, and it came back after clearing 2 weeks later. No 2 heated o2 I think is what it was called. Sort of a crappy or at least too low of an idle.

So I'll try and hook up with Dan (not into splicing and dicing too much), check for rusty nuts (so I can get the right tools if needed) and then get to it.

While I appreciate all the great info on the aftermarket units, I think I'll feed some hungry muts and plug 'n play

 

[94landcruiser]

My mileage dropped significantly when I moved from Ca. to Az. in November I figured it was oxygenated gas and lived with it, when the 02 went at the beginning of Summer and it did not change I did a full tuneup, no change.

I did the sensors no change. I bugged every one for help and did what was suggested, then the HG died and it got a new fuel filter waterpump radiator etc no freaking change!

I banged my head against it (there were no cel or any codes) and then I got a new ground cable end as it had gotten messed up from the numerous r&r's mileage went up almost 3 mpg!

Then I started getting code 26 and weird low idle issues the computer was reporting under range on idle (% of difference from high to low) and a lean condition on both o2 sensors.

AFM seemed the culprit but since the issue is sporadic & they are EXPENSIVE I wanted to wait to be sure. I drove to L.A. and after I got there the truck would not run. I found a junkyard unit & all the issues are gone, I averaged 17.5 on the return trip and am getting 11.5-13 city since.

I'd start at the ground and go from there if I were doing this again. because that was an issue in addition to my AFM.

Good luck.

 

[Romer]

Okay so I finally changed my two o2 sensors, was looking forward to the mileage increase I heard on this thread. Well after three full tanks from the same gas station, my mileage has gone from down from 13.5 to 12.1 mpg The rig is exactly the same as when it had the old sensors. I'm thinking I did something wrong, what say you.

Did you reset the ECU after changing those sensors?

No I did not I'm an idiot. I can reset the ecu by removing the efi fuse right?

Was reading through this thread and don't knoiw what Biff's results were after reseting the ECU.

 

[landtank]

Was reading through this thread and don't knoiw what Biff's results were after reseting the ECU.

doesn't really matter Ken. Any change to the O2 readings would result in a change in FT% within a few minutes after being warmed up. After 3 tanks of gas it would have gotten there for sure.

 

[Romer]

doesn't really matter Ken. Any change to the O2 readings would result in a change in FT% within a few minutes after being warmed up. After 3 tanks of gas it would have gotten there for sure.

Thats why I thought he didn't post up as it was no change. But then you wonder why changing the o2 sensors would decrease his gas mileage.

 

[CJF]

But then you wonder why changing the o2 sensors would decrease his gas mileage.

No kidding.

Heck, at that point I suppose I'd just swap the old ones back in. (Even though that doesn't really make any sense...)

Romer,

Thanks for calling out Biff; I unresolved threads.

Curtis

 

[treehugger]

ok cool

 

[CJF]

ok cool

This is in response to...?

 

[94 Newbie]

Thread back from the dead ! My .02 on the O2's !

I just did mine yesterday ( '94 ) - I had gotten a code 28 & 71 previously and figured it was worth a shot.

A PM to C Dan indicated that mine had already been replaced under the recall ( D'OH ! ) 10/18/95.

So, w/ 12 years & an estimated 135K on them, I figured it was a good time to put new OEM ones in.

I was incredibly lucky as I guess the dealer used never seize liberally and/or the rust penetrant I used 3 times in the past 3 - 4 weeks did it's trick.

The hardest part was getting the connectors unplugged , and the second hardest was figuring out how to get the ratchet up in there - on the left cat (D.S.) , I had to use a box end wrench.

The fill up before the sensors was after a couple of jaunts to & from work , but no a/c useage - 15.41.

Today's fillup after the sensors, and w/ some a/c useage, but mainly highway w/ the moonroof open (75 degrees or so and low humidity - a rarety for Houston ) netted 16.41.

Too early to tell if it is a trend, but one can only hope !


Britt