O2 sensor

[vsII manual]

Have a question for you guys.
I was looking at my o2 sensors last night and when finished i did not plug one back in properly.
I drove off and got the car to operating temp but no engine light came on?
I have heard that sometimes an earthing wire or something in the computer can become detached and not be able to read any o2 sensor codes.
Any ideas?

 

[fitzy2005]

it'll just use more fuel if u didnt plug it back in, u can bridge pins 5 and 6 on ur connecterunder the steering wheel, but i find that absolutly useless, take it to a mechanic and ask if the do tech1 diagnositcs for you

 

[vsII manual]

Yeah but is it strange that the engine light didn't come on when it wasn't plugged in?

 

[Michelson4301]

I have been told by a Holden mechanic that with a 4-wire oxy sensor the earth for the sensor it's self looses continuity through the computer and to put short wire to ground to fix problem. wire functions:- 1 signal, 2 signal earth (instead of using exhaust), 3 12v + for heater circuit, 4 earth 12v - for heater circuit. Check in gregories manual for wire location on PCM plug. *Earth at your own risk*. Be completely sure before connection.

 

[vsII manual]

Oh ok thanks for that! But which one do you earth ? number 2 or 4?

 

[Clacker]

I must be missing something, if pin2 is grounded, then the sensor should be getting its signal earth from there, not the exhaust pipe?

Sure the earth issue isn't computer end?


Clacks

 

[vsII manual]

Mate, im assuming if its the computer end, you could just take it off and earth it to the car body near computer under the kick panel.
I am only guessing though.

 

[Michelson4301]

The tech told me that the computer uses the earth aswell as a sort of reference? and to put a jumper wire to the car body in conjunction with signal earth.