Hey guys, I'm a little confused by this explanation from the ECU.DOC:

0707
"Your Maxima engine is OBD-2 compliant. All Diagnostic Trouble Codes are four digits, with the first is always 0 or 1. Therefore your "77" is actually "0707" which points to the rear Oxygen Sensor.

Your Maxima has three Oxygen Sensors. Two are front sensors, mounted in
the Y-pipe between the exhaust manifolds and the Catalytic Converter. One
is a rear sensor, mounted in the exhaust pipe downstream of the Cat.

When both front Oxygen Sensors are operating normally the rear sensor serves only to keep tabs on the Catalytic Converter. That's the reason your engine is running well. The Engine Control Module (the computer) is not using the signal from the rear sensor to control engine management functions"

Does this mean my rear o2 sensor is shot or my CAT converter? It's says "the rear sensor serves only to keep tabs on the Catalytic Converter" So how do I know if it's the CAT or the o2 itself, please help! I'm suspecting it's my CAT as my odometer is getting around to "time to change the CAT before it blows up" stage(over 100,000 miles)

 

0707 is downstream o2 sensor circuit slow response fault sooo... i have no idea, haha, maybe the cat is getting clogged, or the sensor has build up on it?. i would replace the o2 first because its a lot cheaper, and see if that fixes it.

 

definately the O2 sensor.