Yamaha FX SVHO Won't Start or Dies Immediately

The FX SVHO will not start, or the engine fires briefly and dies. The control unit knows why, and M-JET DIAGNOSTIC lets you see it.

Check chain

• Battery voltage during the start attempt
• Main relay, ETV relay, fuel pump relay, kill switch in the switch status
• Fault memory: camshaft (24), pulser coil (13), throttle valve
• Activate four ignition coils, four injectors and fuel pump

Typical findings

If the engine dies at once, a signal the control unit needs is often missing, for example from the camshaft or the throttle valve. If it cranks without starting, ignition or fuel are in focus. The individual tests show which cylinder or component falls out of line. Important for all tests on the fuel system: good ventilation and no ignition sources. In forums, stalling when the throttle is released quickly is often traced to loose injector connectors or a clamp on the intake hose.

Related topics

• Yamaha FX SVHO: Not Enough Power, Check Boost Pressure
• Buying a Used Yamaha FX SVHO: What Belongs in the Diagnostic Check
• Yamaha WaveRunner Won't Start: Diagnostics
• Diagnostics and fault codes for your Yamaha model
• All Yamaha WaveRunner diagnostics topics

Everything runs via app over Bluetooth, for Yamaha WaveRunners from model year 2002 to today. Learn more about the M-JET DIAGNOSTIC for Yamaha WaveRunner.