Diagnostic Information And Procedures; Fuel System Diagnosis - Suzuki Intruder VZ1500 Service Manual

Fuel System Diagnosis

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 stalls often
(Incorrect fuel/air mixture)
Engine stalls often (Fuel
injector improperly
operating)
Engine runs poorly in
high speed range
(Defective control circuit
or sensor)
Engine lacks power
(Defective control circuit
or sensor)

Diagnostic Information and Procedures

Possible cause
Clogged fuel filter or fuel hose.
Defective fuel pump.
Defective fuel pressure regulator.
Defective fuel injectors.
Defective fuel pump relay.
Defective ECM.
Open-circuited wiring connections.
Defective fuel pump.
Defective fuel pressure regulator.
Defective TP sensor.
Defective CKP sensor.
Defective IAP sensor.
Defective ECM.
Defective ECT sensor.
Defective IAT sensors.
Dirty throttle body.
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 injectors.
No injection signal from ECM.
Open or short circuited wiring
connection.
Defective battery or low battery voltage. Replace or recharge.
Low fuel pressure.
Defective TP sensor.
Defective IAT sensor.
Defective IAP sensor.
Defective ECM.
Defective STP sensor or STVA.
Defective GP switch.
Defective CKP sensor.
Defective ISC valve.
TP sensor out of adjustment.
Low fuel pressure.
Defective TP sensor.
Defective IAT sensor.
Defective CKP sensor.
Defective GP switch.
Defective IAP sensor.
Defective ECM.
Defective STP sensor or STVA.
Defective ISC valve.
TP sensor out of adjustment.
Correction / Reference Item
Clean or replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Check and repair.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Clean.
Repair or replace.
Clean or replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Repair or replace.
Repair or replace.
Repair or replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Adjust or replace.
Repair or replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Adjust or replace.
Fuel System: 1G-4
B940H21704001