Codes 0302 and 0707 (Front Left Heated O2 sensor and Rear Heated O2 sensor I believe). Happened on the way home tonight. I reset the ECU after getting the codes and they didn't come back when I turned the car on (running). I didn't take for a test drive though.. I'll see if they return.

But that's 3 codes in less than a week (0407 first and then 0302 and 0707)!

Any thoughts/comments? Car's running fine. Have had it for 4 weeks now (3 weeks w/o incident)...

 

Strange, after about 4 weekd of driving the ECU should have gone through its cycle and it should have detected the 02 error and throw the code back.

Well the car threw the codes for a reason, I'm guessing it will come back, if you gas milage hasnt decreased then maybe its not defective.

yea that ERG can be a dirty mess if that comes back

 

0302
Diagnostic Trouble code 0302 points to a problem with the Exhaust Gas Recirculation system. The malfunction is detected by the Engine Control Module when no EGR flow is detected under conditions which call for EGR. Possible causes include:
- The electrical harness or connectors (valve circuit open or shorted)
- The EGR valve is stuck closed
- Weak or dead battery
- The EGR passage is clogged
- Faulty EGR temperature sensor circuit
- A leak somewhere in the exhaust system

The EGR Volume Control Valve may be tested with an ohmmeter. Disconnect the electrical connector. Looking at the connector half which is attached to the EGRVCV with the latch at the 12 o'clock position you will see two rows of three terminals. The top row is numbered 1-3, right to left. The bottom row is numbered 4-6, right to left. Measure the resistance between these terminal pairs:
2 1
2 3
5 4
5 6
... all resistance values should be 20.9-23.1 ohms at 68 degrees F.

Reconnect the EGRVCV connector halves. Turn the ignition switch ON OFF repeatedly. Verify that the EGRVCV shaft moves smoothly forward backward according to the ignition switch position.

The Exhaust Gas Temperature Sensor may be tested with an ohmmeter. The specifications are ...
- at 32 degrees F, 0.68-1.11 Megohms
- at 122 degrees F, 0.09-0.12 Megohms
- at 212 degrees F, 0.017-0.024 Megohms



0707
"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.

For more information about Oxygen Sensors go to
http://www.volksparts.com/o2sensors.htm

For specific information about replacing Oxygen Sensors on your Maxima see
the Chilton manual (page 4-13) or the Haynes manual (page 6-14).

In a different thread SprintMax said he got a great price on a replacement factory Oxygen Sensor from Vester Nissan. He didn't give a location or contact information. Perhaps he was referring to Vester Nissan of Clinton NC, 1-800-572-2005. Also www.buyoxygensensors.com

 

0303 is the EGR and the 0302 is the O2 Sensor no?...