How do you manage to torque down o2 sensors? I managed to replace all 4 after removing the intake manifold. I only torqued the bank 2 sensor 2. The others were just torqued by feel with a breaker bar. I would have to check with an endoscope weekly because I intentionally turned to light pressure with a 600 mm breaker bar.

I am seriously thinking of making a special tool to get at those sensors. I have bought 3 type of sockets and they are marginal.

 

Rogelio, you want something like this:

Powerbuilt® 7/8" and 22mm Offset Oxygen Sensor Socket - 647094 | eBay

They make special oxygen sensor sockets that have an arm off to the side and a slit in the socket. This allows you to slide the socket over the wiring and down on to the sensor itself. These hold up much better and will not expand like the full sockets do. This will allow you to torque the sensors to 40 Nm (30 ft-lbs). This is one of the few applications where I would recommend the use of a snap torque wrench (aka, clicker type). That way you simply need to set the torque, take it in the tighten direction till you feel the torque wrench click/shift. The added length of the arm off the side of the socket does not dramatically affect the final torque. If you are truely worried, then torque to 38 Nm (29 ft-lbs). That will take into account the length of the arm.

 

Rogelio, I think you don't need to worry. There's not a lot of torque on the oxygen sensors. Thermo says 40Nm (30lb-ft); that's not cranking it down. These sensors are replacement items - don't set yourself up for problem of not getting one or more out next time 'round. And by the way you did put a dab of anti-seize on the threads, right?

 

Don't overtighten or you may cause damage.

 

I did use the offset socket. But I did not know I can use it with a torque wrench. The one I have is 48mm high and is tight i can't fit a torque wrench. I'm ordering a lower profile one.

Thanks guys.

 

As my teacher said in school 40 years ago. Just tighten it with MF (mechanics feel).

This has worked for me.

 

And bear in mind most people over-tighten, so avoid that.