Rep Power: 0

I purchased a 2002 Honda Civic DX, that had an automatic to manual transmission conversion. The catalytic converter is built into the exhaust. Seem to only have wiring for the downstream O2 sensor (scanner only reads this one). They gutted the cat so it no longer functions. I have been to the junk yard for other parts, some of the 7th gen Civic seem to be running a exhaust with the catalytic mounted externally. I assume I need a catalytic converter, trying to determine the correct one for this vehicle it does have a 1.7 l JDM motor in it.

 
Rep Power: 221

The upstream o2 should be right at the top of the cat. The car would be throwing codes without one. The downstream sensor will be on the pipe after the cat.
if you buy a new cat you might only get a year out of it before it starts throwing codes again

 
Rep Power: 0

The wire harness only has a connector for the downstream sensor. So I assume that if I get a cat built into the exhaust I can plug it like it is now. Trying to purchase the correct cat.

 
Rep Power: 221

So it sounds like when the jdm engine was installed they used the jdm harness. The jdm harness only has the upstream sensor connector. On the jdm and ex cars the downstream sensor connector is on the body harness. Your car is not going to have this. Do you know what computer is in the car?

 
Rep Power: 0

It has a 2003 civic EX in it. I had to replace it had injector issues.

 
Rep Power: 221

You're going to have to add the connector and wires to the ecu if you want to have the dowstream sensor.
What codes do you have?
What exactly are you try to do?

 
Rep Power: 0

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