Yamaha F115A Service Manual page 682

TRBL
ANLS
Items
3. Erratic engine
speed
TROUBLE SHOOTING FOR ELECTRIC FUEL
INJECTION
1. The engine is started, but will not run smoothly. The engine speed
drops during acceleration.
1. Check the high-pressure fuel lines.
1) Check for fuel line
leaks
2) Check the fuel
pressure
3) Check the operation
of the fuel injector
4) Check the diagnosis
cord
2. Check the ignition system.
1) Check the wire harness
2) Check the ignition spark
3) Check the ignition coil
4) Check the ECM output peak
voltage
5) Check the pulser coil output
peak voltage
3. Check the ignition timing.
1) Check the diagnosis
cords
Symptoms
Fuel pressure is
out of specification
9-9
1 Check the 20-A fuse
2 Check the main relay
3 Check the high-pres-
sure fuel pump opera-
tion
4 Check the main relay
drive's ECM output
5 Check the pressure
regulator
1 Check the pulser coil
diagnosis cord
2 Check the engine cooling
water temperature sen-
sor diagnosis cord
3 Check the intake air tem-
perature sensor diagno-
sis cord
E