Suzuki DL650 Service Manual page 404

SERVICING INFORMATION 9-5
ENGINE IDLES POORLY
Symptom, possible causes and remedy
Valve clearance out of adjustment.
Poor seating of valves.
Defective valve guides.
Worn down camshafts.
Too wide spark plug gaps.
Defective ignition coils.
Defective CKP sensor.
Defective ECM.
Defective TP sensor.
Defective fuel pump.
Imbalanced throttle valve or STV.
Damaged or cracked vacuum hose.
ENGINE STALLS OFTEN
Symptom, possible causes and remedy
1) Incorrect fuellair mixture
Defective IAP sensor or circuit.
Clogged fuel filter.
Defective fuel pump.
Defective fuel pressure regulator.
Defective ECT sensor.
Defective thermostat.
Defective IAT sensor.
Damaged or cracked vacuum hose.
2) Fuel injector improperly operating
Defective fuel injectors.
No injection signal from ECM.
Open or short circuited wiring connection.
Defective battery or low battery voltage.
3) Control circuit or sensor improperly operating
Defective ECM.
Defective fuel pressure regulator.
Defective TP sensor.
Defective IAT sensor.
Defective CKP sensor.
Defective ECT sensor.
Defective fuel pump relay.
4) Engine internal parts improperly operating
Fouled spark plugs.
Defective CKP sensor or ECM.
Clogged fuel hose.
Valve clearance out of adjustment.
Adjust.
Replace or repair.
Replace.
Replace.
Adjust or replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Adjust.
Replace.
Repair or replace.
Clean or replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Repair or replace.
Repair or replace.
Replace or recharge.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Clean.
Replace.
Clean.
Adjust.