O2 sensor and the cat?

[dlsalva]

ok, i've got two codes : P0140 O2 sensor no activity and P0421 Warm up catalyst below threshold. if i replace the post cat O2 sensor, should it fix the cat readouts by the ECU?

[MSP #167]

you need a cat p0421 means the cat is shot. i would replace both the cat and 02 sensor.

[91Protege]

Ill 2nd that.

[dlsalva]

damn! i just moved into my new house, and all my tools are in storage. anyone know what a good price would be if i took it to the shop to get it replace? both the cat and sensor? i'm not sure i have ever taken any car into the shop before, so i'm lost. lol

[MSP #167]

well cat's can be pretty expensive, usually around $600-1000. Im not sure what they go for for your car.

[91Protege]

Maybe get a universal cat from ebay and have a muffler shop weld it in.

[zuku26]

gut out the cat and do the non-fouler trick.

[Geo_Allino@yaho]

I have a 98 Protege 1.5L and I have the same error code. I got the P0421 code but the O2 sensors are reading. I know the pre-cat is shot.

Does anyone out there in Mazda land have a good pre-cat I can buy?

Also what does ZUKU26 mean by 'gut the cat and do the non-fowler trick?' I want to get the 'check engine' light to go off and i want to get the best fuel economy possible out of this car.

Please..any suggestions? Would you please email me?

geo_allino@yahoo.com