Yamaha Marine Outboards Factory Service / Repair/ Workshop Manual 225G 250B L250B, Page 358Get this manual
TRBL ANLS Items 2Erratic idling speed
TROUBLE SHOOTING FOR ELECTRIC FUEL INJECTION
Symptoms 1The engine speed is not constant when idling2The engine stalls when the throttle lever is pulled back3The engine stalls when the throttle lever is opened or during outboard operation1Inspect the high-pressure fuel lines1) Inspect for fuel line leaks 2) Inspect the fuel pressure 3) Inspect the operation of the fuel injector 4) Inspect the diagnosis cord 5) Inspect the oxygen density sensor Fuel pressure is out of specification
1 Inspect the 30-A fuse Inspect the high-pressure fuel pump operation Inspect the main relay Inspect the main relay drive's ECU output Inspect the pressure regulator