Engine - Suzuki AN400 Service Manual

9-4 SERVICING INFORMATION

ENGINE

Complaint
Engine will not start
or is hard to start.
Symptom and possible causes
Compression too low
1. Valve clearance out of adjustment.
2. Worn valve guides or poor seating of valves.
3. Mistimed valves.
4. Excessively worn piston rings.
5. Worn-down cylinder bore.
6. Starter motor cranks too slowly.
7. Poor seating of spark plug.
8. Decomp cam not working.
Plug not sparking
1. Fouled spark plug.
2. Wet spark plug.
3. Defective ignition coil.
4. Open or short in high-tension cord.
5. Defective crankshaft position sensor.
6. Defective ECM.
7. Open-circuited wiring connections.
8. Defective spark plug.
9. Defective spark plug cap.
No fuel reaching the intake manifold
1. Clogged fuel filter or fuel hose.
2. Defective fuel pump.
3. Defective fuel pressure regulator.
4. Defective fuel injector.
5. Defective fuel pump relay.
6. Defective ECM.
7. Open-circuited wiring connections.
Incorrect fuel/air mixture
1. Throttle position sensor out of adjustment.
2. Defective fuel pump.
3. Defective fuel pressure regulator.
4. Defective throttle position sensor.
5. Defective crankshaft position sensor.
6. Defective intake air pressure sensor.
7. Defective ECM.
8. Defective engine coolant temperature sensor.
9. Defective intake air temperature sensor.
Remedy
Adjust.
Repair or replace.
Adjust.
Replace.
Replace.
See electrical section.
Retighten.
Repair or replace.
Clean.
Clean and dry.
Replace.
Replace.
Replace.
Replace.
Repair or Replace.
Replace.
Replace.
Clean or replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Check and repair.
Adjust.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.