Front Lambda/O2 sensor removal seem impossible?

[n12nja]

Dear all,

I need to change/or at least clean the o2 sensor precat, I've found it but have no room to put a spanner on it from underneath due to steering rack/body work in the way (see pic) and from the engine bay above it is barely even visible. How on earth do garage's change it? Does it involve unbolting bodywork to get to it?

Thank you for any and all advice! 🙂

D

[DerekHa]

Hi there,

Have never worked on the Yaris but did need to change the pre Cat O2 sensor on a C1 last year and that entailed the removal of the entire front bumper from the car to get full access as the Cat also needed to be replaced. I managed eventually with both ring and open end spanners.

Looking at your images the access is a lot more restricted.

Whilst in the process of sorting the C1's lambda sensor i came across purpose made sockets designed for the removal of these sensors. One these may help you get onto the sensor. Take a look below:

That one's available from Halfords for £14.99. There are other designs of socket that will allow you to get onto the sensor but you may have to work a lot by feel and/or from on top of the engine. Fairly sure there also other designs that accepts the ratchet wrench at a 90 degree offset. Take a look on Amazon they have a lot to choose from.

[Mooly]

10 hours ago, n12nja said:

How on earth do garage's change it?

On a ramp and with the array of tools a typical garage has there looks enough access from underneath. Be under no illusions about how tight it might be after all these years.

I would suggest you look on YouTube under terms such as 'removing stuck 02 sensor' and glean as much info as you can from the numerous videos. Heat and penetrating oil are essentials.

Unless you can get a decent socket/ring spanner and breaker bar on to it then I think your chances of removing it at home are slim. It will be tight, tight, tight.

Good luck and do let us know how you get on.   

[flash22]

its accessed from underneath in the tunnel inline with the exhaust, not under the engine

 

[TonyHSD]

There are variants tools for removing O2 sensors. You can look them on eBay and Amazon and pick the right one for your job. Another important tip: before you proceed, start the engine and let it warm up a bit, 5 min idle it’s enough, the sensor will undo easier 👍