So I swap a JDM b16a into my 97 civic and everything is working properly the motor fires up but it has a low rpm around 700-800 can’t tell which exactly. Wire doing my cam break in I noticed I had a engine light on. So I did the paper clip engine code check and the only code that flashes is 41. I know this has something to do with the O2 sensors but because it’s obd1 idk which O2 sensor is actually being read. Is it the on on the header or the one on the cat?

 

I have a JDM b16a with a obd1 P30 Ecu. I’m throwing code 41 for some reason and I have no clue why. I have a 4 to 1 header with a new o2 sensor that I had to extend myself but I’m still throwing this code. I also have another o2 sensor but it’s super old and is hooked up to the cat. I thought the obd1 ecu doesn’t pick up the second o2 sensor or does this have anything to do with that code 41.


02 sensor at the end of my 4 to 1 header


The header I’m using


Another view of the header


Where I cut and extended the o2 sensor wires


The plug on the engine wire harness

 

Check the order of the four wires in your extended O2 sensor and make sure that they are correct. Next, check the O2 heater circuit fuse in the under dash fuse box.

 

Witch fuse is the o2 sensor? Do you have a diagram or pic of it?

Second would my 4 to 1 header make my o2 sensor not read exhaust correctly causing the check engine light or is it fine to run a 4 to 1 header?

 

Maybe this will help,

https://www.ek9.org/index.php?thread...-heater.73247/