Engine General Information and Diagnosis: 1A-8
Diagnostic Information and Procedures
Engine Symptom Diagnosis
B831G21104001
Condition
Possible cause
Correction / Reference Item
Engine will not start or is
hard to start
(Compression too low)
Valve clearance out of adjustment.
Adjust.
Worn valve guides or poor seating of
valves.
Repair or replace.
Mistimed valves.
Adjust.
Excessively worn piston rings.
Replace.
Worn-down cylinder bore.
Replace.
Starter motor cranks too slowly.
Refer to “Starting System Diagram in Section
1I (Page 1I-1)”.
Poor seating of spark plug.
Retighten.
Engine will not start or is
hard to start (Plugs not
speaking)
Fouled spark plug.
Clean.
Wet spark plug.
Clean and dry.
Defective ignition coil.
Replace.
Open or short in high-tension cord.
Replace.
Defective CKP sensor.
Replace.
Defective ECM.
Replace.
Open-circuited wiring connections.
Repair or replace.
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 injector.
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)
TP sensor out of adjustment.
Adjust.
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 sensor.
Replace.
Engine idles poorly
Valve clearance out of adjustment.
Adjust.
Poor seating of valves.
Replace or repair.
Defective valve guides.
Replace.
Worn down camshafts.
Replace.
Too wide spark plug gaps.
Adjust or replace.
Defective ignition coil.
Replace.
Defective CKP sensor.
Replace.
Defective ECM.
Replace.
Defective ISC valve.
Replace.
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 injector.
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.
Summary of Contents for kq750 2008
Page 2: ......
Page 4: ......
Page 55: ...Maintenance and Lubrication 0B 28 09915 40610 Oil filter wrench Page 0B 12 Page 0B 12 ...
Page 66: ...0C 11 Service Data ...
Page 308: ...1K 5 Exhaust System ...
Page 480: ...4D 6 Parking Brake ...
Page 526: ...6B 13 Steering Handlebar ...
Page 574: ......
Page 575: ......
Page 576: ...Prepared by October 2007 Part No 99500 47020 03E Printed in U S A 576 ...