Subaru EH72 FI - 9. Maintenance and Storage; Daily Maintenance; Periodic Maintenance Schedule

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8-9 ENGINE MISFIRE
Phenomenon Possible causes Remedy
1. Ignition system
1) Improper spark plug gap or damaged electrode Cealn, adjust or replace
2) Ignition coil faulty Replace
3) Damaged ignition system wirings
Check with failure diagnosis
system and replace
4) Poor connection of ignition system wirings
Check with failure diagnosis
system and connect properly
2. Fuel system
1) Lean or rich air/fuel mixture Check and replace throttle body
2) Clogged throttle body
Check and replace
3) Throttle body faulty Check and replace
4) Pulsation damper faulty Check and replace
5) Fuel pump faulty Check and replace
6) Improper gasoline or water infiltration Replace
3. Engine core
componets
1) Valve heat deterioration or improper valve adjustment Adjust or replace
2) Valve spring deterioration Replace
3) Low compression Check, adjust or replace