My cousin gave me his 2000 Honda Accord 2.3L. We live in CA so it is the ULEV version. He gave it to me because the car does NOT pass smog and he don't want to spend $1,500 on a new cat. His "mechanic" said the cat was bad and I need to replace the 02 sensor as well because the one he replaced last time didn't work. To pass smog last time he swapped out the 02 sensor and cat with another car and swapped it back after the test. I know that is illegal and that is why I want to get it done correctly since the car is mine now.

After I got the car I plugged in my BlueDriver scanner and pulled up 4 codes:
2 Confirmed Codes:
-P1167
-P1164

2 Pending Codes
-P1165
-P1164

All of the codes are related to the 02 sensor. After doing some research I found out that the ULEV (California) Honda accord use a different 02 sensor than the rest.

The upstream sensor that I pulled from it says Denso 5540 -11C07.

I tried to look up this 02 sensor and can't find any info it. Could be be that he got the wrong one and is causing all this problem?

Also how can you tell if it is the Cat that is bad or the 02 sensor? I am hoping it is just the 02 sensor.

 

Rockauto lists California-C.A.R.B compliant converters for about $650.

O2 Sensors (F23A4) upstream: $151, downstream: $22

so $823+shipping for the parts to make it pass smog (if all else is OK)

if the exhaust system is factory, or like factory then this should be an easy bolt-in job that pretty much anyone with basic hand tools, a jack/jack stands and level ground can handle.

that saves about $600 compared to the $1,500 job the mechanic quoted.

 

Got the 02 sensor today in the mail. I replaced it and cleared the code. Had the engine on for about 10 minute to warm up the car and ran another test. It was still clear, no CEL and my scanner didn't pull any code.

About how long do I need to have the new sensor in before I will find out if it fixed the problem?

 

Check to see if the readiness monitors have all completed with your scan tool.

 

How long does it normally take for it to be ready? I drove the car around today for about 30 minute of stop/go driving. Did the test and still no CEL.

 

Not so much how long it was driven as it is drive cycles and specific driving conditions are met.

 

Update:
After the driving condition has been met, I got the CEL. Hooked up my reader pulled P0420 code, the cat is bad. I ordered a new one and should be here next week.
For those who replaced the cat, can you use the old gasket or should I get a new one?

 

Best to do new gaskets while you're at it if you got the budget.