Hi Guys,

Need help on an O2 sensor problem. I've done some searching and haven't been able to find the answer.

I have a 1996 SC 300 manual w/o traction control. My check engine light came on and it suggested that it was the O2 sensor pre cat. I had them replaced. Now the light is back suggesting that its the post cat sensor. I think I have 2 post cat O2 sensors. When I looked for the part at rockauto and oxygensors.com it is telling me that I only have one post cat sensor? I'm confused because I thought I had 4 in total (2 pre and 2 post cat). Also, the one post cat appears to have a plate with 2 holes on it. I can't find this part. What am I missing here??

 

You should have 2 in the front (#10,#11) and 2 in the back (#12, #13). I have no idea what this plate is? Is it a block off plate or something?

Jonny

 

I'm confused also. U should have only 4 total? Call the local Lexus dealership or Carson Toyota.

 

i thought it was only 3?

 

Thanks guys. I called the local Lexus dealership and they are saying I have 3 O2 sensors. The parts guy at Lexus said that the plate I was referring to is basically a gasket cover, which I would have to take off to access the sensor.

Jonny - you're drawing clearly shows 4 sensors. Do you know if #12 & #13 are the same part like #10 & #11?

I called my mechanic and he swears there are 4-O2 sensors. However, anyone that looks at a manual tells me there are 3. I didn't think this would be so hard. I just need to get under the car and figure it out and then figure out what if the post cat O2 sensors are the same...

Anyone have a drawing/picture of the under carriage?

 

My Alldata shows that there is 4 sensors, they are also refered to as A/F sensors-air fuel sensor.
You have bank 1 sensor 1, bank 1 snesor 2, bank 2 sensor 1 and bank 2 sensor 2

Sensors 1 are Pre Cat and sensor 2 are posts cats.

 

[QUOTE=TRM09;5439038]Thanks guys. I called the local Lexus dealership and they are saying I have 3 O2 sensors. The parts guy at Lexus said that the plate I was referring to is basically a gasket cover, which I would have to take off to access the sensor.

Jonny - you're drawing clearly shows 4 sensors. Do you know if #12 & #13 are the same part like #10 & #11?






Front Sensor is identified as part# 8946514120 and the rear sensor is part# 8946529895

Bottom illustration shows you which bank is which:

 

EyeSoarer6, that was very helpful. So since I'm looking to get the post cat sensors then I'm looking for Bank 1-Sensor 2 and Bank 2-Sensor 2. Judging by the part #, both sensors are the same. www.oxygensensors.com has the Denso 234-4214 which I think works. I hope this gets rid of my check engine light and can pass emissions and get a new license plate sticker!!!! Wish me luck!

One last question, your figure 5 states V6 FWD. As you know, the SC300 is an I-6 RWD. Is this still correct?

 

Yes, that is correct. its a RWD and I dont really know why they have that diagram listed as a FWD. I entered 96 SC300 and thats what it shows..

 

Thank you! Hope this works!

 

Now I'm confused... The part # I have is 89665-24070.The Lexus dealer said that the O2 sensors (there are only 2 on my car according to them) are the same part...

I called many auto stores around town and most of them say there are 3... I cannot find the other one ???