Am i missing an O2 sensor? - Toyota Nation Forum : Toyota Car and Truck Forums

BeatupRolla · 08-23-2011, 10:51 AM

so i noticed a missing slot, looks to be an o2 sensor slot just below the manifold.. i know there is a o2 sensor on the manifold itself, but the pipe that connects to the manifold has an o2 sensor slot that i am missing, it is facing the front of the car.. the one on the manifold is facing the driver side.. is an o2 sensor suposed to go there? if so where is it suposed to connect to?

maybe this is why i am getting rough idles, rough cold starts and bad gas milage? i felt inside the hole and there was something blocking, not sure if there is suposed to be something blocking or not though.. either way i wanna plug that hole up cause i dont wanna be breathin in those toxic funes while i drive..

also since we are here, how many o2 sensors do we have?

eage8 · 08-23-2011, 11:50 AM

only 1, these cars are OBD-I.

how big is the whole? can you post a picture of it? it might just be a hole for a bolt to only something to it.

BeatupRolla · 08-23-2011, 12:07 PM

lol...... why the heck is it there.... looks like a spot for the o2 sensor though haha

eage8 · 08-23-2011, 12:20 PM

haha, that's wierd.. I have no idea. doesn't look like there is a hole in your exhaust.

it isn't stock :-P

90 GP · 08-23-2011, 05:14 PM

That's where the one on my 90 4afe mounts. Maybe it's a universal type pipe and if sensor mounts there you drill a hole for sensor.

RogueMoog · 08-23-2011, 05:25 PM

On my wagon, that lower hole has the O2 sensor, and the upper location on the manifold itself that you mentioned has a block off plate.

Maybe someone repaired that at a muffler shop, and reused the port for the O2 sensor but didn't bother making the hole for the sensor since they relocated it to the higher port?