Nissan Sentra Service Manual: Three Way Catalyst
If a large amount of unburned fuel flows into the catalyst, the catalyst temperature will be excessively high. To prevent this, follow the instructions.
- Use unleaded gasoline only. Leaded gasoline will seriously damage the three way catalyst.
- When checking for ignition spark or measuring engine compression, make tests quickly and only when necessary.
- Do not run engine when the fuel tank level is low, otherwise the engine may misfire, causing damage to the catalyst.
Do not place the vehicle on flammable material. Keep flammable material off the exhaust pipe and the three way catalyst.
General Precautions
Do not operate the
engine for an extended period of time without proper exhaust ventilation.
Keep the work area well ventilated and free of any inflammable
materials. Special care should be take ...
Fuel (Regular Unleaded Gasoline Recommended)
Use unleaded regular gasoline with an octane rating of at least 87 AKI
(Anti-Knock Index) number (Research
octane number 91). E-85 fuel (85% fuel ethanol, 15% unleaded gasoline) may only
be used ...
Other materials:
P0139 HO2S2
DTC Logic
DTC DETECTION LOGIC
The heated oxygen sensor 2 has a much longer switching time
between rich and lean than the air fuel ratio (A/F) sensor 1. The oxygen
storage capacity of the three way catalyst 1 causes the longer
switching time. To judge the malfunctions of heated oxygen sensor
2, ...
Basic inspection
Diagnosis and repair workflow
Workflow
OVERALL SEQUENCE
DETAILED FLOW
1.INTERVIEW CUSTOMER
Interview the customer to obtain as much information as possible about the
conditions and environment under
which the malfunction occurred.
>> GO TO 2.
2.SYMPTOM CHECK
Verify symptoms.
...
P2138 APP Sensor
DTC Logic
DTC DETECTION LOGIC
NOTE:
If DTC P2138 is displayed with DTC P0643, first perform the trouble
diagnosis for DTC P0643. Refer to
EC-353, "DTC Logic".
DTC No.
CONSULT screen terms
(Trouble diagnosis content)
DTC detecting condition
Possible cause
...
