P0301
Test 1 - Test 4:
Test 5 - Test 7:
Test 8 - Test 11:
Test 12 - Test 15:
Test 16 - Test 17:
Test 18:
SYMPTOM
P0301-CYLINDER #1 MISFIRE
TEST NOTE
This symptom is diagnosed using the test P0300-MULTIPLE CYLINDER MISFIRE
WHEN MONITORED
Any time the engine is running, and the Target Learning Coefficient has been successfully updated.
SET CONDITION
When more than a 1.8% misfire rate is measured during two trips, or with a 10% to 30% misfire rate during one trip.
POSSIBLE CAUSES
- Intermittent misfire
- Visual and physical inspection
- Ignition wire
- ASD relay output circuit (coil)
- Engine mechanical problem
- Ignition coil
- Coil control circuit
- Spark plug
- Checking fuel pressure
- Fuel pump inlet strainer plugged
- Restricted fuel supply line
- Fuel pump module
- Checking fuel leak down
- Fuel injector operation
- ASD relay output circuit (injector)
- Fuel injector
- Injector control circuit
- PCM (ignition system)
- PCM