1998 Johnson Evinrude "EC" 150, 175 FFI Service Manual, P/N 520211, Page 72Get this manual
ILow Maximum RPM SYSTEMCOMPONENT CAUSES ACTIONS
Repair or replace
Substitute known good fuel Isolate using cylinder drop test in aIIC Diagnostic Software andor Timing Light See Action StepsFuel System Pressure Test InjectorSee Section Monitor Fuel System pressure See Action StepsFuel System Monitor Fuel System pressure See Action StepsFuel System
Broken, Restricted Lines, Fittings, Filter Poor QualitySpoil Fuel Faulty Injector or Injector Signal Possible Lean or Rich Cylinder
Fuel System
Faulty Fuel Pump(s) Low Fuel Pressu re Pressure Regulator Stuck Open or MissingLow PressurePossible Lean Top Cylinders Leaking or Restricted Vapor Separator Inlet Valve Faulty or Incorrect Spark Plugs Faulty Coil or Lead