Rep Power: 0

Hi folks!

First post here, so be kind

I'm looking to get a used Civic and I just checked out this 2000 EX coupe that looked really clean and nice. The guy sounded like he knew his way around the car, and had custom rims and exhaust pipe. He had all the bells and whistles, just high miles - 192000. When I went to drive the car, he said that the CEL is on because he changed the exhaust but didn't change the O2 sensor. I'm not sure if the 02 sensor needs to be upgraded just because he put a muffler on and that's why I'm here.

Is he trying to make his way around? Or is he being truthful? He said he's ready to put the stock exhaust on and that will get rid of the CEL.

 
Rep Power: 234

What do you mean by exhaust? The catalytic converter? Hi-flow exhaust? You're supposed to change the sensor with the cat but, it should go back to normal with the old sensor after a new cat is put on. Have him take you and the car to Autozone and have the code read to know for sure.

If it's a hi-flow cat then try this trick: https://www.civicforums.com/forums/2...on-w-pics.html