DRTYLNDY

Hello. I am new here and pretty new to Toyota also. I have a 2002 Sequoia that has a bad O2 sensor. It is sensor 1 in bank 1. My question is where is cylinder 1 drivers side or passengers? I do know it is the sensor before the cat just not sure which side. Any help would be greatly appreciated.
Johan

fillsrunner4

It should be the very first sensor in the exhaust system pre-cat. I dont know sequoia's well but i dont amagine theres more than 2 or 3 sensors in the exhaust. One EGR most likely, two o2's on pre one post cat. Bank 1 sensor 1 is the pre cat 02

fillsrunner4

Does your car run kinda funny? cause the first 02 sensor is for a/f mixture

DRTYLNDY

Nope she runs perfect just the CEL is on. Brought it to Autozone and they said it is the O2 sensor precat but there are 2 of them on the 4.7. So it states it is the one closest to cylinder 1. That is where I need help which side is cylinder 1 on. Thanks

fillsrunner4

not sure what side cyl. 1 is on. Do you know where the 02 sensors both are. one is pre cat so its that sensor dont worry about closest to cly 1 cause the post cat on cant be closer if you know what i mean

DRTYLNDY

The problem is there are 2 O2 sensors pre cat on the 4.7. One on the right side and one on the left side. I need to find cylinder 1 so I replace the correct sensor.

fillsrunner4

ok i see. Sorry i dont know the one you need