Yamaha FX1100: Idle Hunts or Engine Stalls

At idle the FX1100's speed hunts, or the engine dies when docking. That often fits the bypass valve that regulates idle air. M-JET DIAGNOSTIC shows you how the control unit reacts.

How to proceed

• Fault memory: code 84 reports the bypass valve, code 99 irregular intake air
• Live data at idle: engine speed, intake pressure, throttle angle
• Teach the idle after the valve or throttle body has been cleaned
• Read the memory again after the ride

Why learning is needed

After cleaning, the control unit no longer has matching learned values. Without new learning the idle often stays unsteady although everything is clean. Learning does not replace a repair, though: if a hose is loose or the intake manifold leaks, the problem remains. For all tests the engine may only run with a water supply.

Related topics

• Yamaha FX1100: No-Wake Mode and Steering Switch Report Faults
• Yamaha FX1100 with Catalytic Converter (2007/2008): Exhaust Manifold Temperature
• Yamaha WaveRunner Rough Idle: 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.