Hi!

I have an Acura Integra GS with 97,000 miles on it and the check engine light came on last week. I took it to the dealer who reported that the cause of the light was OBD code 0420 (Catalyst System Efficiency Below Threshold). He performed some cheks and on not finding anything obviously wrong reset the light. He also told me that I would need to replace the Catalytic Converter if the light came back on.

After driving for 300miles the light came back on. This time I took it to Autozone to check if it was the same error code and it was. AutoZone suggested that it could also be the O2 sensors.

Catalytic converter costs about $1000 and O2 sensors are $600. Is it possibe to zero-in the real problem.

Also if it was the catalytic converter wouldn't I fail the emission test?

Any feedback would be highly appreciated.

Thanks,
Rishi

 

What year Integra is your car?

 

if its your cat then you will probably fail emissions. the dealer usually replaces the whole exhaust system when they replace your cat so thats y its so expensive. i had the same problem and bought a used cat here on h-t for 60$. if its the secondary o2 sensor on the cat then i have a spare i would be willing to sale.

 

Yeah, don't buy the overpriced dealer parts. Look on http://www.acuraparts247.com first, then look at aftermarket parts. There's high-flow catalytic converters available from Random Technologies and others for much less than $1k. You can also buy aftermarket O2 sensors for far less than $300 each. Search around.

 

If the cat is working properly the outlet temp with be about 100°C hotter than the inlet temp. Use a infared thermometer to measure.

If the temperature checks out then you probably have a bum O2 sensor or 2.