Yamaha FX SVHO: Not Enough Power, Check Boost Pressure

The FX SVHO feels weaker than usual. With supercharging, a look at the intake pressure helps, which M-JET DIAGNOSTIC shows live.

What you compare

• Intake pressure (kPa) at standstill and at full throttle
• Engine speed and throttle valve angle at the same time
• Intake air temperature and ignition timing
• Fault memory for sensor and knock messages

Evaluation

If intake pressure at full load does not rise clearly above ambient pressure, the supercharger apparently does not deliver. That gives a workshop an inspection task. If it rises normally but power is missing, ignition timing, temperatures and fuel supply move into focus. The app cannot prove supercharger damage, but it supplies the numbers that make conversations with the workshop more concrete. Typical of a worn supercharger clutch is an engine that runs smoothly but hangs at about 5000 to 5500 rpm on the water while intake pressure stays close to ambient. According to forums a hand test of the clutch is unreliable; even a worn clutch can pass it.

Related topics

• Buying a Used Yamaha FX SVHO: What Belongs in the Diagnostic Check
• Yamaha FX SVHO: Reset the Maintenance and Flush Warning
• Yamaha WaveRunner Power Loss: Finding the Cause
• 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.