Name is Bob, new to the Honda scene, don't own one but trying to help my kids keep theres running. 2004 civic Ex 1.7L . They come to me with engine light and local auto parts tells me it's bank one sensor one, however the parts idiot can't tell me if that is pre or post CAT. After we argue for about 10 minutes and I do searches I get mixed information. I just then assume that the pre sensor is the issue, as that is what my technical experience (not with Honda) tells me. He brings out three sensors and says what is my engine code, I tell him D17A2, well that is not listed I'm wrong he says. So we walk out to the car , look at the timing cover and what do ya know D17A2! I get in my car and leave before I k Ock the guy out. So go to Rock auto, Amazon, to find the part but still so confusing, the item that comes up doesn't have the correct connector on it meaning I need male and it's female. Now the car was bought used so it could be hacked up. It looks like it's not. Any help I'd appreciate. I am searching also for definitive answers as I'm into this job now $300 and cannot seem to solve it.

 

Do you still have the CAT converter on the car??

What mods do you have done or is it just stock?

 

Yes motor is stock. Took the car to Honda and had a diagnostic check done, it came back no signal on the bank 1 sensor 1 (pre cat) and post CAT came back heater not working. The service manager told me you cannot put after market sensors in that motor also. Looks like a possible electrical harness issue to me.

 

Do you have a multimeter so you can check to see if you have a broken wire. I would check from the ecu plug to each O2 sensor connectors.

Make sure you have the ground signal, heater signal, and voltage reference.