The situation is my Catalytic Convertor has started rattling

post-cat O2 sensor wire is cut, the sensor itself is bodgy welded into the pipe after the cat, would be hard to get out

It appears if I order a new Cat from Rock auto, they come with a thread to accept the O2 sensor into the Cat itself ?

Not sure what is the exact difference between O2 sensors,

On the '96, I have an idea they may be the same Pre & Post Cat ?...do they have 95 or 97 plugs?

I would ignore this except it will not pass rego, due to the rattle, need a functioning cat to be legal

(doesnt throw a check engine, but does have a P0138 code)

If I order one from Rock Auto...is there any reason to avoid cheap?... any economical brands known to be ok ?

not happy "wasting" money on a p!ssy issue like this..but what can you do

 

Cheap stainless steel adapter, thread type 18mmx1.5



This is how I opened mine like a clam shell and removed the loose catalyst bricks. A welder is required. The sensor spacer keeps the ecu from reporting a failed cat.

 

That was my first thought, dummy wire the O2 sensor, codes are not read, so ok there for rego

I still might try I guess, however, by the time I cut the cat out, and the shields I thought it might be noticeable trying to weld up that old metal, and so it doesnt leak, and a real pita.

The inspection mechanic is diligently thorough too

my exhaust mate flat out refused to do the cut & shut welding for me. He said $A350 for the full job

I can get a Cat for about $130 delivered, he would probably R&R for $50

The Inspection authorities make it hard to keep old cars on the road. Maintenance must be good

 

On my '96 (build date 8/96) the up stream took NGK 23121 and the down stream took NGK 23014.

 

That sensor just tells the computer when your cat goes bad, so it can light the warning light. It does not affect the operation of the engine,