Possible causes

– Faulty Air fuel ratio (A/F) sensor 1 Bank 1
– Faulty Air fuel ratio (A/F) sensor 1 heater Bank 1
– Fuel pressure
– Faulty Fuel injector
– Faulty Air Flow Meter

Tech notes

If one or more sensors are replaced the Engine Control Module (ECM) Mixture Ratio Self-Learning clearing procedure must be perform.

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

Altima Sedan
Altima Coupe
Armada
Frontier
Cube
Maxima
Murano
Pathfinder
Quest
Rogue
Sentra
Titan
Versa
Xterra
Nissan Factory Service Bulletin OBDII Code P1284

When is the code detected?

The A/F signal computed by ECM from the A/F sensor 1 signal is shifted to the rich side for a specified period.

Symptoms

– Engine Light ON (or Service Engine Soon Warning Light)
– Possible rough engine idle

P1284 NISSAN Description

The Air Fuel Ratio (A/F) sensor is a planar dual-cell limit current sensor. The sensor element of the A/F sensor is the combination of a Nernst concentration cell (sensor cell) with an oxygen-pump cell, which transports ions. It has a heater in the element.

The sensor is capable of precise measurement