Suzuki AN400 Service Manual page 71

Condition
Engine will not start or is
hard to start (No fuel
reaching the intake
manifold)
Engine will not start or is
hard to start (Incorrect
fuel/air mixture)
Engine idles poorly
Engine stalls often
(Incorrect fuel/air mixture)
Engine stalls often (Fuel
injector improperly
operating)
Engine stalls often
(Control circuit or sensor
improperly operating)
Engine stalls often
(Engine parts improperly
operating)
Engine noisy (Excessive
valve chatter)
Possible cause
Clogged fuel filter or fuel hose.
Defective fuel pump.
Defective fuel pressure regulator.
Defective fuel injector.
Defective fuel pump relay.
Defective ECM.
Open-circuited wiring connections.
TP sensor out of adjustment.
Defective fuel pump.
Defective fuel pressure regulator.
Defective TP sensor.
Defective CKP sensor.
Defective IAP sensor.
Defective ECM.
Defective ECT sensor.
Defective IAT sensor.
Valve clearance out of adjustment.
Poor seating of valves.
Defective valve guides.
Worn down camshafts.
Too wide spark plug gap.
Defective ignition coil.
Defective crankshaft position sensor.
Defective ECM.
Defective throttle position sensor.
Defective fuel pump.
Defective ISC valve.
Defective IAP sensor or circuit.
Clogged fuel filter.
Defective fuel pump.
Defective fuel pressure regulator.
Damaged or cracked vacuum hose.
Defective ECT sensor.
Defective thermostat.
Defective IAT sensor.
Defective fuel injector.
No injection signal from ECM.
Open or short circuited wiring
connection.
Defective battery or low battery voltage. Replace or recharge.
Defective ECM.
Defective fuel pressure regulator.
Defective TP sensor.
Defective IAT sensor.
Defective CKP sensor.
Defective ECT sensor.
Defective fuel pump relay.
Fouled spark plug.
Defective CKP sensor or ECM.
Clogged fuel hose.
Valve clearance out of adjustment.
Too large valve clearance.
Weakened or broken valve springs.
Worn tappet or cam surface.
Worn and burnt camshaft journal.
Engine General Information and Diagnosis:
Correction / Reference Item
Clean or replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Check and repair.
Adjust.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Adjust.
Replace or repair.
Replace.
Replace.
Adjust or replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Repair or replace.
Clean or replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Repair or replace.
Repair or replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Clean.
Replace.
Clean.
Adjust.
Adjust.
Replace.
Replace.
Replace.
1A-8