HYOSUNG GV250 EI Service Manual page 86

Complaint
Engine runs poorly Defective engine internal / electrical parts
in high speed range. 1. Weakened valve springs.
2. Worn camshafts.
3. Valve timing out of adjustment.
4. Too narrow spark plug gaps.
5. Ignition not advanced sufficiently due to poorly working timing
6. Defective ignition coils.
7. Defective pick-up coil.
8. Defective ECU.
9. Clogged fuel hose, resulting in inadequate fuel supply to injector.
10. Defective fuel pump.
11. Defective SAV solenoid.
12. Clogged air cleaner element.
Defective air flow system
1. Clogged air cleaner element.
2. Defective throttle valve.
3. Sucking air from throttle body joint.
4. Defective ECU.
Defective control circuit or sensor
1. Low fuel pressure.
2. Defective IAT sensor.
3. Defective pick-up coil.
4. Defective IAP sensor.
5. Defective ECU.
6. Defective SAV solenoid.
Symptom and possible causes
advance circuit.
85
SERVICING INFORMATION 7-2-3
Remedy
Replace.
Replace.
Adjust.
Adjust.
Replace ECU.
Replace.
Replace.
Replace.
Clean and prime.
Replace.
Replace.
Clean.
Clean or replace.
Adjust or replace.
Repair or replace.
Replace.
Repair or replace.
Replace.
Replace.
Replace.
Replace.
Replace.