Possible causes

– The EGR volume control valve circuit harness is open or shorted
– EGR volume control valve leaking or stuck open
– Faulty EGR temperature sensor

Tech notes

Start by cleaning the EGR valve, if the code persist it may be necessary to replaced the EGR Valve.

There is a factory service bulletin for the following Nissan Models:

2004-2005 Nissan Maxima
2004-2005 Nissan Quest
2005 Nissan Altima
Nissan Factory Service Bulletin OBDII Code P1402

Symptoms

– Engine Light ON (or Service Engine Soon Warning Light)

P1402 NISSAN Description

This system controls flow rate ofEGR led from exhaust manifold to intake manifold. The opening of the EGR by-pass passage in theEGR volume control valve changes to control the flow rate. A built-in step motor moves the valve in steps corresponding to the ECM output pulses. The opening of the valve varies for optimum engine control. The optimum value stored in the ECM is determined by considering various engine conditions. The EGR volume control valve remains closed under the following conditions.
– Engine stopped
– Engine starting
– Engine idling
– Low engine coolant temperature
– Excessively high engine coolant temperature
– High engine speed
– Wide open throttle
– Low battery voltage

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NISSAN Technical Service Bulletins for P1402 code