Engine Warning Light - Chapter 2

Went for a Club run up to the Bonnie Doon Hotel for lunch and back to Melbourne eastern suburbs (325 km round trip with plenty of 100 kph speed). The engine warning light came on about 40 kms from home on the way back, car continue to drive fine. Checked it out today using my OBD-Link MX+ Bluetooth adapter and their phone software with a little help from ChatGPT. Says it is likely the O2 sensor/wiring after the cat converter (95% confidence level). Suggested I reset the ECU and see if it comes up again. Seems like a common problem for these cars that are 20+ years old and not driven much? An MGF on the same run had the same issue!
Regards
Mikee
2004 MGTF 160

Since you would appear to be it Melbourne, you could drop by my place in Bentleigh East to use my Pscan if you need to.
PM me you ph # for my contact details.

Is there a test you can do with oxygen sensor to checked it is okay, resistance, etc?
What is the thread on these sensors? I see the workshop manual says spanner to use is M22 crows foot.
Cheers
Mikee
2004 MGTF 160

There are dedicated tools to remove O2 sensors  which are easily found on the likes of Amazon, ebay and automotive shops for not a lot of $$$, or you may already well have something in your toolbox that will do the job well enough for you, I suggest 1st you have a try with what you have before rushing out and buying something you don't need, Sometimes they will come loose easily, with a sort sharp hammer tap on the tool, but they can often be bloody hard to undo.
A note to the wise: if you feel what ever you're using feels like it may slip and round of the hex head....STOP!......Don't risk rounding the hex off.........You will need to get the proper tool.

The dedicated tools can vary from simple tools to more elaborate ones to get into awkwardly place sensors to whole sets, some with thread chasers to clean up shiity treads the are even ones to be mounted on an Air hammer of seriously stubborn  sensors!

Whatever you do ........don't use a bloody shifter (adjustable spanner)

 

 

 

 

 

 

 

Now as for testing the O2 sensor, they can be tested with OBD diagnostics or you can do some tests with a multimeter, for this you should refer to the values in the workshop manual with is downloadable for this site.
In your case Mike you can borrow my sensor tools, workshop manuals etc, as you live near by!




 

A good tip is if you get the correct socket with the cutaway for the cable put a jubilee clip around it once it is in place.
Stops it opening up.

By making the”wire slot” wider, less damage is done on removing the old & refitting the new. Obviously this would weaken the tool, allowing it to open if excess grunt is applied & this is where TA22’s tip with the jubilee clip comes in.
I made a sleeve which just slipped over the socket, making the assembly very solid.
Having gone to all the effort the bloody sensor came away easily.
M

+1 for using the right tool. Lambda sensor removal socket or variation on that search phrase into Ebay will bring them up. They are too expensive and you can always sell it on if you dont expect to be using it more than once. Dont try to use an adjustable. The right tool, a modicum of turning force and it will move.