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:
P0300, P0301, P0302, P0303, P0304 Misfire
DTC Logic
DTC DETECTION LOGIC
When a misfire occurs, engine speed will fluctuate. If the engine speed
fluctuates enough to cause the crankshaft
position (CKP) sensor (POS) signal to vary, ECM can determine that a misfire is
occurring.
Sensor
Input signal to ECM
ECM function
...
Precaution
Precaution for supplemental restraint system (srs) "air bag" and "seat
belt pre-tensioner"
The Supplemental Restraint System such as “AIR BAG” and “SEAT BELT PRE-TENSIONER”,
used along
with a front seat belt, helps to reduce the risk or severity of injur ...
Cooling fan control
SYSTEM DIAGRAM
SYSTEM DESCRIPTION
ECM controls cooling fan speed corresponding to vehicle speed, engine coolant
temperature, refrigerant pressure,
air conditioner ON signal. Then control system has 3-step control
[HIGH/LOW/OFF].
Cooling Fan Operation
Cooling Fan Relay Operation
Whe ...