Code 41 shoule be pretty much limited to the heater circuit of the O2 sensor. Not a whole lot of unrelated problems can set that one off.

Since you had exhaust work, you might want to look at the wiring down at the sensor. They may have pulled on the wiring, rubbing thru some insulation somewhere within the wiring that belongs to the car.

What are the other smog numbers? Sometimes you can play them off against each other. For example, advancing your spark timing a little bit can improve CO & HC while making NOx worse.

 

I had the exact same issue.

Replaced O2 sensor with Bosch. Drove from Los Angeles to Vegas and back, about 600 miles, and then guess what... Got Heated O2 sensor CEL.

Pulled Bosch, (returned it as faulty) and got OEM NTK O2 sensor. No more O2 sensor problem!

Hope that helps. I double checked the Bosch O2 sensor with a multimeter, and it read as faulty according to Honda's Tech Manual.

That was about 5 months ago, still no CEL!

Oh as a side note, when I got the CEL, the car ran like crap. It seemed like it was running out of gas. Bogging out. Also got Fuel supply CEL due to Bosch O2 sensor.

 

I was getting the CEL code 41 BEFORE I took it in for the exhaust. There's the possibility that I did something when I changed the O2sensor back in May when the 41 code first started. After a month the 41 is back, same symtoms. Coasting in gear with low RPM's.
I got a good a sticker but the numbers were worse after the super and the injector cleaner. I'm in need of a timing belt so that will get done next and hope that improves the problem because I'm prolly not getting the best gas mileage right now.

 

I think I'm going to try the OEM NTK because my gut tells me it's the Bosch. I returned and exchanged the first Bosch for the same code 41 and code 40.

 

the code 41 will only come on if theres a problem with the heater in the O2 sensor or if theres no power getting to the sensor with the O2 the exhaust doesn't need to be there jsut the O2 plugged in...to test unplugged O2 with a multi meter check then pins to of where the 2 black wires are (heater ) with the key in the on position 1 should have 12v on it the other goes back to the ecu if no power check fro blown fuses as the heater runs on a different fuse also how old is your cat?

 

Not sure, I just got it in April 08 with 225k on it. I got just about 229k on it now. Replaced the muffler at about 228k. the repair shop checked the exhaust and didn't say anything about the cat, but I didn't ask either. Can't see them shying away from a buck though.