1G-5 Fuel System:
Diagnostic Information and Procedures
Fuel System Diagnosis
B931H21704001
Condition
Possible cause
Correction / Reference Item
Engine will not start or is
hard to start (No fuel
reaching the intake
manifold)
Clogged fuel filter or fuel hose.
Clean or replace.
Defective fuel pump.
Replace.
Defective fuel pressure regulator.
Replace.
Defective fuel injectors.
Replace.
Defective fuel pump relay.
Replace.
Defective ECM.
Replace.
Open-circuited wiring connections.
Check and repair.
Engine will not start or is
hard to start (Incorrect
fuel/air mixture)
Defective fuel pump.
Replace.
Defective fuel pressure regulator.
Replace.
Defective TP sensor.
Replace.
Defective CKP sensor.
Replace.
Defective IAP sensor.
Replace.
Defective ECM.
Replace.
Defective ECT sensor.
Replace.
Defective IAT sensors.
Replace.
Dirty throttle body.
Clean.
Engine stalls often
(Incorrect fuel/air mixture)
Defective IAP sensor or circuit.
Repair or replace.
Clogged fuel filter.
Clean or replace.
Defective fuel pump.
Replace.
Defective fuel pressure regulator.
Replace.
Damaged or cracked vacuum hose.
Replace.
Defective ECT sensor.
Replace.
Defective thermostat.
Replace.
Defective IAT sensor.
Replace.
Engine stalls often (Fuel
injector improperly
operating)
Defective fuel injectors.
Replace.
No injection signal from ECM.
Repair or replace.
Open or short circuited wiring
connection.
Repair or replace.
Defective battery or low battery voltage.
Replace or recharge.
Engine runs poorly in
high speed range
(Defective control circuit
or sensor)
Low fuel pressure.
Repair or replace.
Defective TP sensor.
Replace.
Defective IAT sensor.
Replace.
Defective IAP sensor.
Replace.
Defective ECM.
Replace.
Defective CKP sensor.
Replace.
Engine lacks power
(Defective control circuit
or sensor)
Low fuel pressure.
Repair or replace.
Defective TP sensor.
Replace.
Defective IAT sensor.
Replace.
Defective CKP sensor.
Replace.
Defective IAP sensor.
Replace.
Defective ECM.
Replace.
Summary of Contents for 2009 LT-A500XP
Page 2: ......
Page 4: ......
Page 14: ...00 9 Precautions ...
Page 224: ...1E 3 Engine Lubrication System EXHAUST SIDE INTAKE SIDE I931H1150003 02 ...
Page 304: ...1K 4 Exhaust System ...
Page 346: ...2D 5 Wheels and Tires ...
Page 438: ...3D 26 Propeller Shafts ...
Page 482: ...4D 6 Parking Brake ...
Page 512: ...5A 28 Automatic Transmission ...
Page 624: ...Prepared by December 2008 Part No 99500 44080 03E Printed in U S A 624 ...