MIABLKSC4

hello all, i've already searched on the O2 sensor topic. both my main O2 sensors are out. i've seen that for the most part the two sites to get them from are www.oxygensensors.com and www.global4autoparts.com. now, the deal is i already talked to lexus dealership and they quoted $130 per sensor. i'll be installing them myself so i won't be paying an arm and a leg. i've read all the other threads on this subject and i'm still a little unclear as to how well the aftermarket denso, walker, nkt, and all those O2's work. i would rather not pay the dealership $130 so if someone could let me know if there are some others that are OEM and will work just the same and get rid of this trac off light and CEL, and where i can actually get them it would greatly be appreciated. thanks again guys. new to the board and constantly learning everytime i read these threads.

/Aerostar\

iTrader: (2)

I got both my main O2 sensors off www.oxygensensors.com for $57 shipped. They are the Walker Universal ones. Very very easy to install and they work fine . If you need any help installing them, you know who to ask. Where in FL are you?

BLK13X

My O2 sensor is gone on my car too (well, so I think, very bad fuel economy and everything else has been checked). Just wondering, how hard is it to install? I was gonna go OEM Toyota parts except they are AUD$300 each from Toyota, an aftermarket one is $130 or so but apparently needs a new flange to bolt into position and needs rewiring to fit.

/Aerostar\

iTrader: (2)

The new O2 sensors come with a new flange which fits perfectly. As for rewiring, all it takes is splicing in the ONE new wire, very very very simple. The kit even comes with a clamp connector and some heat shrink shielding. As for the actual process, all you gotta do is remove the intake (from the airbox to where it enters the TB) and remove the exhaust manifold heatshield. (this is for the SC3's by the way). The whole thing should take about an hour

MIABLKSC4

hey aerostar, i'm in coral gables/miami. i go to university of miami. if the walker ones work fine i'll just do that then. i may need you to help me with the splicing. unfortuantely school is about to end and i have to head back home to mississippi, along with the car. but only for the summer. i'll probably end up doing the install there. now i see on oxygensensors.com that they have two walkers, an OE and an universal. does it really matter which one or should i just get the OE ones?

/Aerostar\

iTrader: (2)

Just get the universal one man, dont waste your $$$. Im in sarasota right now, so we're a good 3-4 hours apart. As for splicing the wires, it is beyond simple. Unclip the O2 sensor clip, cut the old O2 sensor off as close to it, then strip the old wiring and connect it to the new O2 sensor. Then all you have to do is clip it back in.

EUROJulian

Denso make OEM sensors for Toyota and Lexus, so if you have choice in aftermrket offerings Denso would be a best choice.

If you are in Miami I can hook you up though. PM me if interested....

EUROJulian

Areostar is the man, I like his can do attitude

As for sensors wire splicing, you have to solder it over the splice. We are talking here small voltages and we need good connection.
Just as a thought, Toyota O2 sensors connectors are gold plated. It is that importand.

BTW I think gent have SC400, those can be wicked to remove if rusted....

dean s

you can pick up a socket for o2 sensors at your auto parts store real cheep!!! SAVES A LOT OF TIME and the wires are color coded 'just read the derrection that come with your o2 sensor" put the car up on jack stands you need lots of room under there..I cut the wires about halfway down first just to get them out of the way..it a piece of cake, but get the socket!!!!!!
good luck

/Aerostar\

iTrader: (2)

Thanks man And as for the soldering over, I wish I knew that. But my check engine light did turn off and stay off so Im not really concerned. However, for anyone looking to do this, soldering over the connection would be a good idea if you're willing to do it.

rabbit415

How many 02 sensors do i have to replace? all of them or just two.

dean s

just the two front ones the rear are for your"cat."I believe ,{its been awhile } but you really don't have to worry about them !

EUROJulian

You should. Check light will not sense problem until it is out of range, preferably open or short.

Lack of MIL doesn`t mean computer senses correctly oxygen content in exhaust gases from your engine. Like I said before, voltage produced by the sensor is minimal, bellow one volt, any resistance on the way will afect the readings.
In addition electrical noise from elswhere in the engine/car may afect the readings. That`s why sensor leads are shielded too.

Way to check the sensor for proper operation is to compare oscyloscope waveforms during controled test run. There are no other valid way.

dean s

so what your saying ,is that even though the check engine light isn't on, the engine might stll be getting the wrong fuel oxygen mixer or?pardon my ignorance but I have trouble understanding this area of the mechanics of the car ! do we have to accually take it to a mechanic to test the read out even tho we change the o2 sensor ourselves???and what are the draw backs if we do not?

EUROJulian

Sure entirely possible. Generaly engine may be running like crap and you will not get MIL to go on.

Stick with OEM parts if you have limited understanding and you should be OK. If you decide to experiment on your car, make sure you know exactly what you are dealing with so you can closely duplicate factory engineering. I think this is as simple as I can put it.