2000 LS400 - O2 Sensor choice (80K on clock)

[Guest]

Hi Guys (& Gals)

On my way up to Seattle airport to collect family when I got a engine management warning light. I "baby" my Lexy, so I pulled into a local Toyota dealership and had them run the diagnostic. It is my front (drivers side) O2 sensor. They stated car will still run fine (and it does) but I have lost the reading from that sensor and hence warnings etc. if Catalytic fails :) Typically I was charged $75 for running the test!!! (Sadly my tester was at home) and they proceeded to quote me $278 to order a replacement!!!

I've been on several websites and found a variety of manufacturers Denso, Walker, Replacement? etc. and prices quoted from $200+ down to $45 for a pair (Driver & Passenger - front). I think I will replace both to be safe.

My question is, can anyone recommend a good oem replacement and anything else I should be aware of when replacing them? Do I need to replace rear as well?

Regards, Phil

Edited November 4, 2016 by Guest
Because I didn't search first! :(

[Guest]

Just found this post from 2007

"I have a 98 LS and I had to replace the left side first O2 sensor. I's under the seat your have to pull up the carpet and remove the gas pedal (just pull hard toward the seat it will pop off) the you will see the wire for it . Not a big job total of about 1 hour. I bought a Denso replacement for $65.00 no big deal I think the dealer wanted around $280.00 "

That will teach me to search first before posting :( 

This is a G8 source of info, thank you ALL members.

[Exhaustgases]

Yes go Denso, and you will not have to pull the carpet for the front or upstream O2 sensors. Pulling the carpet up is for the rear or downstream sensors. I haven't done it but pulling the carpet may not be all that fun, that is to do it right, with out wrecking something. I would think to do it right may mean removing the seat or seats.

But then I don't know all that much about the newer gen LS's, on the old ones the front or upstream ones are easy.

[Guest]

Thanks Bob, I thought that may be the case but I haven't looked underneath yet.

The write ups referring to removing carpets etc. seem to be needed to access the plug/socket on the harness. Does that mean the Front (pre-cat) Sensor(s) plugs are actually accessible from below?

Thanks again.

[Exhaustgases]

Yes on the gen 1's the upstream ones are quick and easy to get to.  And I can't see your Gen being much different, that write up may have been calling the far rear one the first one I don't know. When I did my one car O2 sensors I got them at Rock auto, about half the price of local auto parts house. Its the way to go if you can wait.

[sha4000]

No need to remove the carpet to change the front (upper) O2 sensors.

[Guest]

Thanks Guys, info much appreciated.

[M.Yasir]

Hi Phil and welcome to the forum

i have 1998 with me, O2 sensors before the Cat. are easy, lift the car up and direct access, but after the Cat. are cumbersome i cannot think why lexus did that, since the electrical socket of the sensor is going up in the body from the exhaust,

Wiring harness is underneath the drivers side carpet, now in order to remove the carpet you have to take the gas pedal out,

The passenger side O2 sensor is also connecting up in the body and the harness underneath the carpet but in this case it is easy

I have purchased Bosch sensors from rock auto, since they came with the exact length of wire

PS: are you really sure that at 80k miles on the ODO your O2 sensors are fried?, i have 250k miles on my ODO and my O2's are working just fine (although i have purchased new ones but i am yet to install them, i did tried to install them here at a gas station mechanic told that i will not be able to install on the drivers side since it is difficult, so i left it as it is)

[Guest]

Thank you, I was advised it was my Front Driver side O2 Sensor by my local Toyota Dealership, who ran the diagnostic for me. I will check again before purchasing new Sensor. Only 80K but nearly 17 years old! :)

 

[M.Yasir]

Yes Phil you are right 17 years old but these cars have a tendency to just live and keep on living for years to come by, i think the age of the car should be ignored completely when dealing with LS

[vissine]

I replaced all 4 O2 sensors (Denso) a few years back. I bought without connectors, cut the wires and solder them back. All were replaced within 2 hours. 

[Guest]

Hi Guys, thought I would post an update. I DID replace both forward O2 Sensors with a couple purchased via Amazon (suspect they were "China" brand but at 40% the price of Denso items.

Anyway have had 3.5 years of trouble free motoring, but "Lexy" through up a P0125 code last month 😞 Checked Thermostat, Coolant Temperature Sensor etc. and all passed good?

After reading several posts on here I checked my O2 Sensor Heater voltages, Yep one was DEAD... Now put in Denso Sensors and she is running fine 😄

Remember, you get what you pay for! 😏

[paulo57509]

1 hour ago, philmstar said:

Hi Guys, thought I would post an update. I DID replace both forward O2 Sensors with a couple purchased via Amazon (suspect they were "China" brand but at 40% the price of Denso items.

Anyway have had 3.5 years of trouble free motoring, but "Lexy" through up a P0125 code last month 😞 Checked Thermostat, Coolant Temperature Sensor etc. and all passed good?

After reading several posts on here I checked my O2 Sensor Heater voltages, Yep one was DEAD... Now put in Denso Sensors and she is running fine 😄

Remember, you get what you pay for! 😏

There's a lot of garbage being sold on Amazon and ebay.  In my experience, any unbranded, cheap, made in or being sent from China item is to be avoided like Wuhan city.

I've tried more than a few sets of those LED headlight retrofit bulbs in a few of my cars and the failure rate out of the box and a few months down the road is horrendous.  I've even had cell phone charger cords and counterfeit phone and camera batteries that were DOA.