Rep Power: 0

Hey guys. I've got a 2005 Honda Civic LX Special Edition that has its check engine light on. It started about 2 months ago when i got my oil changed at walmart and they replaced the air filter. I doubt that's significant, but i'll include it anyways. Shortly after the oil change, the light came on. i took it to Autozone, and they read the code. Bank one Sensor one A/F 02 sensor. 400 bucks down, replaced the 02 sensor at the honda dealer. A week later, light came back on, took it back in, and they replaced the 02 sensor again to ensure it wasn't a bad sensor out of the box. another week later, check engine light came back on. So, the guys at the dealer did a system relearn on it, to make sure it wasn't mis calibrated. 24 hours later, it came back on. And sure, throughout the week it would go on and go off...just never stayed consistent. I took it back to the dealer, and they said its the ECU in the car that wasn't sending the 02 sensor enough voltage. So, i replaced the ECU. 800 bucks later. a week went by. Check engine light came back on. I have no idea what could be wrong with it. What's the next step? I could really use your guys's help. I trust you all more than any of these bullshit dealers.

 
Rep Power: 233

Which code exactly? It does matter.

For now, check grounds, wires to the sensor, and the connector real good. Look for burnt insulation or a striped wire. Look for loose wires at the connector.

Also check for an exhaust manifold leak. Take the heat shield off and look for cracks or a bad gasket.