Oxygen Sensor replacement - Toyota Nation Forum : Toyota Car and Truck Forums

Toy_Dreamer · 03-03-2011, 08:49 PM

Good day to you all.

So, I have a bad rear O2 sensor that has been verified from a shop here in town. I need to replace it but they, the shop, wants to charge me $300 for the whole deal!! That's insane! The reason behind it all is that it's a California car, therefore requiring a California O2 sensor. He also said that it need to be direct wire (which I wouldn't think would be too hard because I know quick a bit of wiring, stuff)

I guess my question to you guys is that: Do I need a California O2 sensor for this car? I have an idea of how to take it off and put a new one on, but any tips would help for when I get the O2 sensor.

Thanks!

bronzemaxell · 03-03-2011, 09:24 PM

last time i replaced CA emission a/f ratio sensor cost me $180 from toyota stealership after $25% discount www.toyotaoemparts.com

federal emission = oxygen sensor
CA emission = air /fuel ratio sensor

need 22mm closed ended 6 point wrench, or special o2 sensor removal socket that has a slit on the side.
the sensor is probably fused to the exhaust, either run the car until hot, or use a portable torch to heat the exhaust nut, not the sensor will make the job a lot easier because heat will cause the iron to expand, wear protective to avoid burning.

there is a chance the sensor or the nut thread will strip, and hard to reach sensor area make the job even more difficult, sometime it is better to leave it to the pro.

thaharlequin · 03-03-2011, 10:15 PM

It's about $50-$75 for a downstream O2 sensor off of ebay/rock auto/etc and $5-10 for the oxygen sensor socket at harbor freight. Just run the car a bit before you take the old sensor out. The only problem I've had was improper wiring instructions with the sensor I got from Kragen back in the day, but that was easy enough to figure out (just switched power for the heater and the line for O2 sensor voltage). If you have trouble unclipping the connector pull the O2 sensor first so you can get a bit of slack, and don't forget a bit of anti-seize before installing the new one.

Toy_Dreamer · 03-03-2011, 10:42 PM

Thanks for the information guys! But I must reinstate, I live in Wisconsin and it's a California car, am I able to do this with any O2 sensor? Or does it HAVE to be a California sensor? Being CA emissions and all...

carsrus · 03-03-2011, 11:05 PM

If its a CA emissions car you need a CA sensor. Either way its a simple unscrew and plug in the connector deal. Really easy to do.

***fenixus*** · 03-03-2011, 11:11 PM

by saying REAR you mean the upstream sensor in rear bank of V6 or you mean the downstream (post-cat) sensor under car? if the latter than in both Federal and California emission specs the post-cat sensor is same cheap oxygen (thimble type) sensor, around $60 from ebay or amazon for Denso OEM.

if that is about the upstream sensors, than California emission specs NEEDS Air Fuel Ratio Sensor (around $110 from ebay or amazon for Denso OEM) instead of federal one. California type ECU can't really work with federal type upstream sensors, different programming.

check your Denso part numbers here:
http://www.densoaftermarket.com/cata....php?part=o2sn

and look for them on amazon.com or ebay.com, just make sure you are buying actual Denso with that part number and not some "compatible" brand.

Toy_Dreamer · 03-04-2011, 12:26 AM

Quote:

Originally Posted by fenixus

by saying REAR you mean the upstream sensor in rear bank of V6 or you mean the downstream (post-cat) sensor under car? if the latter than in both Federal and California emission specs the post-cat sensor is same cheap oxygen (thimble type) sensor, around $60 from ebay or amazon for Denso OEM.

if that is about the upstream sensors, than California emission specs NEEDS Air Fuel Ratio Sensor (around $110 from ebay or amazon for Denso OEM) instead of federal one. California type ECU can't really work with federal type upstream sensors, different programming.

It's downstream. Sooo, look for a normal (not a CA) one then, right?

***fenixus*** · 03-04-2011, 12:36 AM

Quote:

Originally Posted by Toy_Dreamer

It's downstream. Sooo, look for a CA one then, right?

downstream, rear, post-cat (under car) is same for either Federal or CA emissions specs.

gen4 camry (both V6 and i4, both FED and CA) use Denso 234-4137 as the downstream sensor.

$70 free shipping on amazon:

Amazon

DIY here:
DIY : Downstream Oxygen O2 Sensor replacement

oxygen sensor socket you can borrow from local Autozone (refundable deposit required).

Toy_Dreamer · 03-04-2011, 12:38 AM

Awesome! Thanks man! This sure beats spending $300...

ghettosled · 03-04-2011, 11:28 AM

douse the old sensor with plenty of PB blaster. im sure that thing will be rusted in there pretty good.

Stillrunning · 03-04-2011, 12:29 PM

Quote:

Originally Posted by ghettosled

douse the old sensor with plenty of PB blaster. im sure that thing will be rusted in there pretty good.

As has been mentioned get the exhaust system hot first, but don't be surprised if you need a torch for more heat.

Toy_Dreamer · 03-05-2011, 01:35 AM

Quote:

Originally Posted by Stillrunning

As has been mentioned get the exhaust system hot first, but don't be surprised if you need a torch for more heat.

I think I'll just torch them - knowing me I'll probably burn myself with the entire exhaust system hot. Added to that I don't have much gas and am saving it for my trips to work, with gas prices and all...

speedy25 · 03-05-2011, 08:00 AM

There are only two styles of O2 sensors. Heated and unheated. They dont know which state they are living in. Only the emissions SPECIFICATIONS are different for CA and the rest of the world. If it fits and has the right number of wires you're good to go.

The hard question is why do they make those sensor sockets only in 3/8 drive when you need at least a 1/2' breaker bar to get them loose!!

-SP