Hey everyone,
So in another post I asked about a/f & O2 sensor replacement. Well I ordered the front a/f sensor and got it replaced, then a few days later i got a p0420 code. So i ordered the rear sensor and replaced that also. So here is where I am confused. The a/f ratio and 02 sensor look different than what I pulled out of the denso boxes.
These I pulled from my 2000 4runner 4WD Cali Emissions (verified by Vin)
Left = Upstream location, i think its been replaced before with a different denso sensor, no toyota part number printed on sensor
Right = Downstream location, think its either oem or replaced by a different oem sensor, printed on sensor is Toyota 89465-35510
These where inside the Denso Boxes:
Left = UpStream (234-9002), Right = DownStream (234-4153)
Comparing them, the A/F sensors look different, which makes me believe that the previous owner replaced the A/F sensor with just an 02 sensor to pass emissions..... (if that's even possible), or toyota changed the design, but I am not sure of that, so I am not sure if i bought the right part or not.
Same goes with the DownStream O2 sensor, the shape looks different, it does not have that cylindrical bulge on the shaft of the sensor. Not only that, the part number Toyota 89465-35510, when googled shows it is for a Sequoia. Maybe the part number is old and that specific sensor was useable on different vehicles, including the 4runner, and was changed later on, I am not sure.
Can anyone clarify if these original or replacement parts are correct?
I have a gut feeling the previous owner had his "personal mechanic" just put whatever in there.
Thanks
So in another post I asked about a/f & O2 sensor replacement. Well I ordered the front a/f sensor and got it replaced, then a few days later i got a p0420 code. So i ordered the rear sensor and replaced that also. So here is where I am confused. The a/f ratio and 02 sensor look different than what I pulled out of the denso boxes.
These I pulled from my 2000 4runner 4WD Cali Emissions (verified by Vin)
Left = Upstream location, i think its been replaced before with a different denso sensor, no toyota part number printed on sensor
Right = Downstream location, think its either oem or replaced by a different oem sensor, printed on sensor is Toyota 89465-35510
These where inside the Denso Boxes:
Left = UpStream (234-9002), Right = DownStream (234-4153)
Comparing them, the A/F sensors look different, which makes me believe that the previous owner replaced the A/F sensor with just an 02 sensor to pass emissions..... (if that's even possible), or toyota changed the design, but I am not sure of that, so I am not sure if i bought the right part or not.
Same goes with the DownStream O2 sensor, the shape looks different, it does not have that cylindrical bulge on the shaft of the sensor. Not only that, the part number Toyota 89465-35510, when googled shows it is for a Sequoia. Maybe the part number is old and that specific sensor was useable on different vehicles, including the 4runner, and was changed later on, I am not sure.
Can anyone clarify if these original or replacement parts are correct?
I have a gut feeling the previous owner had his "personal mechanic" just put whatever in there.
Thanks
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