O2 sensor code coming back
I just joined the forum. About a week ago, the check engine light popped on my 92 Sc300. I jumped the OBD1 and got code 21 and 28, which correspond to the Main O2S & Heater Signal. So I went ahead and replaced the two upstream O2S with OEM part #89465-29505. The code cleared right away so I didn’t test the old O2S. But today the check engine light came back on and I got the exact same code. Does anyone know what should I do about this?
Thanks in advance
Last edited by ziiiro2011; May 10, 2022 at 12:00 PM. Reason: Adding a thank you line



