O2 Sensor - Code P0135 - Replace all?

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On my 06 the sensor situation is evidently a bit different. The rear, downstream sensors I can get from amazon / denso.

But the front sensors in my year model are now called air/fuel mix sensors, and are $170 each...and can't find that Denso makes them.

Of course, I could be very wrong...

Sent from my iPhone using IH8MUD
 
ntsaint said:
On my 06 the sensor situation is evidently a bit different. The rear, downstream sensors I can get from amazon / denso.

But the front sensors in my year model are now called air/fuel mix sensors, and are $170 each...and can't find that Denso makes them.

Of course, I could be very wrong...

Sent from my iPhone using IH8MUD
Click to expand...

Interesting. Must have had to adapt the O2 to the air injection system.
 
Ouch, that makes a little more sense then. Sucky. What kind of mileage are you getting now? I'd say unless you're consistently in the 11s-12s or recently saw a marked drop in mileage, don't bother for that kind of money.
 
Bought the Denso ones from RockAuto. Had a 5% off coupon, plus was buying several other things, so on the balance the sensors were just a little cheaper than Amazon. The sensors were great, but getting mine out turned out to be tougher than expected.

1999 LC, 186k miles, first time replacement. No codes, just especially poor mileage during the past year than I had in the previous ~11 years.

I decided to try this out without the crow's foot. BAD MOVE. Popped by my former auto-dealer friend's house, and he only had a crow's foot up to 19mm / 3/4". Nope...that didn't work. So I went after them with a few open end and crescent wrenches, including a "stubby" (awesome, short-handle crescent wrench). The passenger side was harder to get too, but easily broke loose. The connector was the problem there. Really worked over my abs and neck muscles, but after 15 minutes of working at it different ways, it finally separated. The driver's side connector came loose, but no matter how I tried to loosen it, it would just not budge. After maybe an hour of working on this one, my neighbor had a bright idea...let's hack that think apart and then put a socket on it. 10 minutes later with a small sawzall, I popped my 22mm socket onto it and had it loose and out of there.

All in all, what should have been a 1-hour job MAX, this being my first time pulling the sensors along with setting up to do a little other maintenance and checking, took me about 2 1/2 hours. I can honestly say that a crows foot wrench would have saved me at LEAST an hour and a whole lot of pain and frustration. I should have listened to the other posters that said to get it. Lesson learned.

After about 15 miles of driving (after battery cable was pulled for ~hour), I filled up the gas tank and we'll see where the mileage goes. I only got through a tank every 2 weeks or so so it's going to be a month before I have one tank down (mostly a throwaway while the engine adjusts) and a second tank down to see if it made a real difference.

I'll also be putting in a new fuel filter this weekend, end-links for the front roll bar and if I can get to it, the upper and lower heater hoses are worn out and need replacing, none of which should change the mileage. Hopefully I can find some posts here on doing the hoses. I have the repair manual but it just doesn't seem to give me enough information on draining out the radiator for this job.
 
TheFuzz said:
Ouch, that makes a little more sense then. Sucky. What kind of mileage are you getting now? I'd say unless you're consistently in the 11s-12s or recently saw a marked drop in mileage, don't bother for that kind of money.
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I'm averaging 11mpg in town, 13-14 highwway, and I'm driving like a little old lady trying to maximize it. My fuel costs are low (2-3 tanks per month, max), but the truck used to get 13-16 (even with the 275/70/18 tires), and it's bugging me.
 
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Yeah, you're basically in the same boat I'm in. Just today, the gas light finally came on from the first tank I put in after doing the sensors 6 weeks ago. No improments yet. :doh:
 
Have you guys cleaned the MAF? I'm going to try that. I pretty much have a stock 00 with 265/75/16 tires and I'm at 14 on the freeway. I was at 16-17 BEFORE the O2 sensor install, even with the CEL light on. I wonder if these Denso units from Amazon is the culprit.
 
I clean mine once a year usually. It does help some, but mine wasn't that dirty the last time I sprayed it off.

If I were at 17mpg and had an 02 CEL, I would have left it alone! :lol:
 
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I posted a few months ago after I replaced my front sensors. The first few tanks of gas after the change, I had some of the best mileage I've had, about 2 mpg better than usual. It has backed off a bit, but I am still getting about 1 mpg better than before. I've got a clean MAF, new air filter and run 295s at 37 psi. I changed mine because I threw a code. I wouldn't have otherwise.
 
phsycle said:
Have you guys cleaned the MAF? I'm going to try that. I pretty much have a stock 00 with 265/75/16 tires and I'm at 14 on the freeway. I was at 16-17 BEFORE the O2 sensor install, even with the CEL light on. I wonder if these Denso units from Amazon is the culprit.
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Put the old ones back in! Id kill for 16-17.
 
I used the Denso's from Amazon and my millage went from 13-14 to 15-16, so as far as I am concerned the Denso's did their job!
 
I think the outdoor air temperature has a non-trivial effect on fuel mileage.

Short trips in subfreezing temperatures adversely affect average mileage.

I have been using my cruiser as a grocery-getter in Anchorage for the past month, where the temperature has averaged about 10 degrees F. In the past month I have gone 210 miles on 22.3 gallons, so that's about 9.4 mpg.

However, I think a significant fraction of that fuel is used while waiting for the truck to warm up.
Sometimes the exhaust smells rich right after start-up, but this goes away as soon as the engine comes up to temp (< 10 minutes). (I see why the canadian guy wanted the water heater for his diesel, but my 4.7 V8 seems to do a fine job of warming itself up after about 10 mins).

I guess the air-fuel-ratio feedback mechanism does not function until the engine warms-up (i.e.-open loop mode). Would replacing the O2 sensors help them to reach operating temperature faster?

I definitely get better mileage ~15 mpg in the summer time.

Bottom Line: I'm not using much fuel because I don't drive very much overall. It is totally worth spending the money on gas to have ATRAC and those heated leather seats in a vehicle that is built like a very reliable tank.
 
Thanks ya'll!!! saved me some cash.

My Bank 2, before cat went out.

Stealership wanted $159 for the part and 1.5 hours labor (about $400!!!)

With this thread, esp. that great schematic, I went to autozone had them read the code, got the correct 02 sensor and came home. Also got a 22mm socket.

The front passenger side is a bugger to get to. I could see it from inside the engine bay but ended up removing the plastic tray on bottom and pulling back the splash guard in the wheel well.

1. from my crawler underneath I was able to undo the plastic clip. I put vice grips on the old plastic portion and pushed down hard with my thumb and it came fairly easy.
2. for the spark plug looking end I took a 22mm open ended wrench and went in just above the frame rail (through opening I made with splash guard being pulled back) and it came loose. (I had put PB Blaster on it in the driveway while it was still hot) came loose easy.
3. I used a Bosch replacement and it came pre greased with a plastic cap over the greased male portion. (Make sure you screw it in first and then the plastic clip)

I am a .5 or 1 banana mechanic. I have done simple things like a new GR starter on my 40 and this was a joke. How do stealerships sleep at night charging 1.5 hours labor for this 20 minute job?

here is a picture of the actual part I didn't see it in the thread yet and wanted to contribute....thanks

new on right, old on left...old was a denso new is a bosch

im driving to NOLA from Jackson Ms thursday will report fuel mileage then
02 sensor.webp
 
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Just replaced the bank 2 pre-cat o2 sensor. Easiest method was to remove the wheel, the clips holding the rear half of the fender liner and fold the liner back forward of the hub. From there squeeze the base of the wire connector, it may help to use A small screwdriver inside the connector to free the retaining clip. Using the 22mm o2 sensor socket (which you'll really want to use), remove the old sensor. Literally 20 minutes start to finish.
 
Well, "easiest" is hard to say. I just replaced both pre-cat sensors from underneath as the belly pan was off for another procedure. I have plenty of space underneath with my OME kit on the truck. Soak things with PB Blaster a bit before hand.

The one on the right is cake, just takes a minute with my big hands to separate the connector. A proper O2 sensor socket and a ratchet with a flex head and that thing was done in just a few minutes. Driver's side only took a couple more minutes to bend the heat shield back with a pair of channel-locks to provide space for the socket. New one installed and I bent the heat shield back in place and attached connector.

As far as which method is easier; hard to say. Six of one and half a dozen of the other. All in all, it's a one-banana job with the right tools.

Glad things went smoothly for you. Took me more time to track down my O2 sensor socket than the job itself !!!

abrooks said:
Just replaced the bank 2 pre-cat o2 sensor. Easiest method was to remove the wheel, the clips holding the rear half of the fender liner and fold the liner back forward of the hub. From there squeeze the base of the wire connector, it may help to use A small screwdriver inside the connector to free the retaining clip. Using the 22mm o2 sensor socket (which you'll really want to use), remove the old sensor. Literally 20 minutes start to finish.
Click to expand...
 
Pre sensor install I was getting 10-11 mpg,after install and headed out of town (with some around town) I got 12 mpg, in downtown NOLA I got 12. Highway headed home we achieved 16 mpg!!!!!! (cruise control at 73 mph)
 
is 234-4169 the correct part number for an 05 Lx? looked on amazon and it said those dont fit my truck????? i am still getting 15.1 - 15.4 on the interstate but around 10 in the city and i used to get 16.5/12.5, but i just turned 175,000 and my cel and VSC lights are staying on i puled the codes last night but didn't write them down, duh. I know its one of the O2 sensors from the last time i had it serviced, but my MPG was fine then so i was going to take the time, but i drive about 700miles a week right now and the extra MPG would help $$$
 
wow, scanned through this thread, right off the bat im going to be installing four new O2's just to be safe and clean my MAF sensor. Just picked my LC up a few weeks ago and ive been just cleaning her up and doing all sorts of maintenance. I rahter just get this out of the way.

nice thread btw
 
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