1. How do you remove the primary o2 sensor connector from the bracket? I have already disconnected the other cable but not sure how to remove the connector out of the car.

2. When checking the primary o2 sensor voltage live with an obd2 reader, with engine running, it fluctuates from .02 to .800, is this normal? I got P0131 with engine, vsa, and ! light came on, but then they all went away by themselves.

 

with a wrench?

 

I don't think a wrench is needed, and a wrech can hardly fit in there either on the top or from the bottom of the car. It looks like the connector is clipped on to something. It is in a tight space so it was hard to see. It is clipped on to the engine, between the engine and the rear engine mount.

Someone got to have replaced primary o2 sensor before.

 

You shouldnt have to remove it from the bracket. Unplug the 02 from the car side and it should be all you need (thats the way it was on mine) then take the wrench and unscrew it from the exhaust. Primary being the first one and not the one by the cat.

 

I did unplug it from the car side by reaching down from the top, but the connector from o2 side is still attached to something there. Will have to try again. Thanks

 

I think I know what you mean by the bracket holding the wire from the 02 sensor to the car.. just so it doesn;t get caught up on anything. Just slide it away from the car IIRC.

 

Thanks. I will try that. It may be just hanging on a hook. I meant the 4pins connector of the o2, that is what I am having trouble with.

 

So in post 5 you say you unplugged it but here you say you didnt?

 

it is unplugged from the engine side connector which is the female side, but how to un-attach the o2 connector, which is the male side from where it is hanging and take it out. The 4p connector on the o2 is attached to something that I can't remove it. I just tried, and couldn't remove it. it must have another clip on the connector snapping into something.

 

Here's how to remove the primary O2 sensor. From the top, in the engine compartment, behind the engine, look down carefully you will find the green cable with a grey plastic connection, press the tab with your thumb, jiggle it a bit and pull it up. that is the female connector, runs to the engine. the male connector, is the o2 connector, runs to the exhaust, it stays intact where you just remove the female connector. To remove the o2 connector, there is another tab on the bottom of the o2 connector on the opposite side connecting to a short metal bracket, feel it with your index finger, press the tab and pull it down. Now, get under the car, use a 10mm wrench to remove a bolt that holds the L metal bracket that secures the green cable. Now the cable is free and you can remove the o2 sensor with a 21mm wrench.

There is no way you can remove the female connector with one hand if the o2 male connector is not being secure to something. Even if the pluged connectors are on the table, you need to hands to seperate them.

 

anyone have pics?

 

it is completely normal for an o2 sensor's voltage to constantly change
from my text book: "A good oxygen sensor should be able to produce a value of less than 300 millivolts and a maximum voltage above 800 millivolts"

 

It is Not Normal in my case. It has conditions to determine whether it is bad or not. In my case, it was BAD o2.