I've got an issue with my 2011 Rav4. 190k miles, 2.5L inline 4 cylinder. I got an engine code for the O2 sensor (downstream). the 4WD and Traction Control lights also came on along with it. I got a new sensor, replaced it, reset the codes and the next day all 3 of the same lights came back on again. What could be causing this?
Provide the code here.
Clarification: Was the sensor replaced with an OEM one?
@Yaser. Sorry I forgot about that. Lol the code it tripped was P0138 and P0136. P0138 says "O2 sensor circuit High voltage Bank 1 sensor 2" and P0136 says "Oxygen sensor circuit (Bank 1 Sensor 2)"
NTK sensor from Auto Zone
This is not the OEM. Get a Denso sensor. You can buy it almost everywhere, just make sure you choose the correct one (based on your vin#)
Ok. so I was a little confused when I got the first new sensor at Auto Zone. Yes, it was NTK but under the notes, it said "Actual OE part." Does NTK make OEM parts or could that have just been an error in their system? Maybe it meant it was similar to the OE part?
It is not the actual OEM. As I mentioned before, the OEM part for your car should be made by Denso.
Ok. here's what's even more odd, Auto Zone has a Denso sensor, no surprise there, but under the notes for that one (downstream sensor), it says it's an aftermarket part. I'm starting to think that maybe their notes aren't very accurate after all. Denso only makes OE parts, right? the part number for this one is 234-4622
I don't know your vin# but you can use this website to find the correct part number:
https://www.toyota.com/owners/parts-service/parts
Well realize one things OBD2 codes are relatively generic codes. Now there are literally dozens of things that can trip that code. Other than a bad sensor itself, if you used a non OEM aftermarket sensor, go back and get it original equipment sensor and pray that fixes it. Because if not it's probably time to see a mechanic. As I said, there's dozens of things that can trip that code. It isn't necessarily the sensor itself
I made sure to get an OE part for the replacement. The sensor I replaced with was an NTK sensor from Auto Zone. I did however notice after resetting the codes (unhooked the battery for a few mins since I didn't have a scan tool), the car idled kind of rough upon startup, however it was only for a few minutes, and after a little bit of driving, it went back to idling like normal. The other issue that I have noticed ever since I've had the car was that whenever I'm driving at around 30-40 mph and lightly pressing the throttle, I'll hear a rattling / vibrating noise that sounds like it's coming from the exhaust. I don't know if it's just a heat shield rattling or something more serious, but when I press the throttle a little bit harder, it goes away. Overall the car still runs very well, and if it wasn't for the engine lights, I wouldn't even be able to tell that something was wrong with it.