TROUBLESHOOTING
9-2
Incorrect idling speed or mid-to-high speed
—
Water or foreign material in fuel,
degraded fuel
Change fuel.
Loose spark plug
Tighten the spark plug to the spec-
ified torque.
Loose cylinder head or cylinder
Tighten bolts or nuts on cylinder
head and cylinder to the specified
torque.
Damaged cylinder head gasket
Replace the cylinder head gasket.
Incorrect valve timing
Adjust the valve timing.
Incorrect valve clearance
Adjust the valve clearance.
Worn valve guide
Replace the valve guide.
Bent, damaged, or stuck valve
Replace the valve.
Poor contact between valve and
valve seat
Reface the valve-to-valve-seat
contact.
Fatigued or broken valve spring
Replace the valve spring.
Worn, damaged, or stuck piston
ring
Replace the piston and piston
rings as a set.
Seized or damaged piston
Replace the piston and piston
rings as a set.
Worn or damaged cylinder bore
Replace the cylinder, piston, and
piston rings as a set.
Symptom
Possible cause
Actions
Spark plug does not produce a
spark
Incorrect spark plug gap
Adjust the spark plug gap.
Worn or damaged spark plug
Replace the spark plug.
Defective spark plug cap
Replace the spark plug cap.
Defective ignition coil
Replace the ignition coil.
ECU failure
Replace the ECU.
Low fuel pressure
—
Measure the fuel pressure.
Fuel leakage
Check the fuel passage. Repair or
replace as necessary.
Clogged fuel pump
Clean or replace the fuel pump.
Cracks or damage in fuel pump
Replace the fuel pump.
Fuel pump malfunction
Refer to “TROUBLESHOOTING”
Fuel not supplied
Failed or clogged fuel injector
Replace the fuel injector.
ECU failure
Replace the ECU.
Symptom
Possible cause
Actions
Содержание YZ450FP 2023
Страница 6: ...EAM20162 YAMAHA MOTOR CORPORATION U S A YZ MOTORCYCLE LIMITED WARRANTY...
Страница 10: ......
Страница 44: ...MOTORCYCLE CARE AND STORAGE 1 32...
Страница 61: ...TIGHTENING TORQUES 2 16...
Страница 66: ...CABLE ROUTING DIAGRAM 2 21 Frame and engine right side view 1 A B 2 C 3 4 D 5 6 E 7 9 8 13 12 10 1 11...
Страница 68: ...CABLE ROUTING DIAGRAM 2 23 Handlebar front view 6 5 D 4 3 2 B 1 A 8 F H I 5 10 G 7 E 8 7 E 2 3 9 C J...
Страница 72: ...CABLE ROUTING DIAGRAM 2 27 Frame and battery top view 2 1 B 5 4 3 A 7 4 E 6 D 2 3 C...
Страница 74: ...CABLE ROUTING DIAGRAM 2 29 Rear brake right side view 8 C C C D D E E F G B H 4 3 2 1 7 6 5 A A...
Страница 76: ...CABLE ROUTING DIAGRAM 2 31...
Страница 154: ...REAR BRAKE 4 38 system Refer to BLEEDING THE HYDRAULIC BRAKE SYSTEM on page 3 26...
Страница 194: ...CHAIN DRIVE 4 78...
Страница 254: ...SHIFT SHAFT 5 58 TIP Align the punch mark a on the shift shaft with the punch mark b in the shift pedal 1 1 1 2 2 a b...
Страница 267: ...CRANKCASE 5 71 6 45 mm 1 77 in 7 60 mm 2 36 in 8 75 mm 2 95 in 1 2 3 3 4 5 6 6 6 8 8 8 7 7 7 LT...
Страница 278: ...TRANSMISSION 5 82...
Страница 300: ...IGNITION SYSTEM 8 1 EAM20142 IGNITION SYSTEM EAM30277 CIRCUIT DIAGRAM...
Страница 305: ...IGNITION SYSTEM 8 6...
Страница 306: ...ELECTRIC STARTING SYSTEM 8 7 EAM20143 ELECTRIC STARTING SYSTEM EAM30279 CIRCUIT DIAGRAM...
Страница 310: ...CHARGING SYSTEM 8 11 EAM20144 CHARGING SYSTEM EAM30282 CIRCUIT DIAGRAM...
Страница 311: ...CHARGING SYSTEM 8 12 2 AC magneto 3 Rectifier regulator 4 Engine ground 5 Frame ground 6 Battery 7 Fuse...
Страница 313: ...CHARGING SYSTEM 8 14...
Страница 314: ...FUEL INJECTION SYSTEM 8 15 EAM20145 FUEL INJECTION SYSTEM EAM30284 CIRCUIT DIAGRAM B...
Страница 339: ...FUEL INJECTION SYSTEM 8 40...
Страница 340: ...FUEL PUMP SYSTEM 8 41 EAM20146 FUEL PUMP SYSTEM EAM30287 CIRCUIT DIAGRAM...
Страница 356: ...ELECTRICAL COMPONENTS 8 57...
Страница 372: ...SELF DIAGNOSTIC FUNCTION AND DIAGNOSTIC CODE TABLE 9 15...
Страница 382: ...CHASSIS 10 9...
Страница 384: ......
Страница 386: ......
Страница 387: ...B YZ450FP 2023 WIRING DIAGRAM BHR 2819U 10_W D indd 1 2022 08 09 13 16 06...
Страница 388: ...ON OFF PUSH FREE PUSH FREE B YZ450FP 2023 WIRING DIAGRAM BHR 2819U 10_W D indd 2 2022 08 09 13 16 06...