A throttle that hangs, sticks, or suddenly surges is almost never the engine losing power — it's the throttle body's butterfly valve not moving the way it's supposed to inside its bore. That valve has to rotate freely across a narrow clearance to the bore wall, and anything that narrows that clearance or adds drag to the shaft turns a light, linear throttle pull into something that either resists opening or snaps wide open with too little input. Add in an intake track that's ingesting salt-laden air every ride, and that combination explains why this is one of the more common complaints on saltwater-run skis.
Why the Valve Sticks
Two separate contamination sources cause most of the trouble, and they build up differently.
The first is crankcase and combustion byproduct — oil vapor and unburned fuel residue pulled back through the engine's breather system settle on the throttle bore and valve edge, where heat cycles them into a varnish-like film. This is the same mechanism that gums up carburetor throttle plates, just happening downstream in a fuel-injected or direct-injected setup instead. Over time that film builds up thick enough at the valve's edge that it no longer seats or swings cleanly, and idle gets erratic or the valve hangs slightly open before finally releasing.
The second is salt. On saltwater riders, aerosolized salt spray gets drawn in with intake air and deposits on every surface downstream of the filter, including the throttle shaft and its bushings. Salt is hygroscopic — it pulls moisture out of the air — so instead of drying to an inert dust, it stays damp and corrosive, working on the throttle shaft bushings and bore surface. That corrosion adds physical drag to the shaft rotation and can pit the bore itself, so even after a cleaning the valve may not swing as freely as new.
Cleaning It Correctly — and the Distinction That Matters
Before touching anything with a solvent, figure out whether the ski uses a cable-actuated throttle body or an electronic (fly-by-wire) one. Sea-Doo's iTC (intelligent Throttle Control) system, used across most of its lineup since the late 2000s, and similar electronic throttle setups on newer Yamaha and Kawasaki models replace the mechanical cable with a throttle position sensor (TPS) at the handlebar and another at the throttle body, both feeding the ECU, which then drives the valve with a small electric actuator. Cable-actuated bodies are simpler — a physical cable pulls the valve open against a return spring, no sensor involved in the actual valve movement.
That distinction matters because aggressive solvent-based throttle body cleaners — the kind sold for automotive use with strong degreasing agents — can migrate into the TPS housing on electronic units and attack the internal sensor contacts or seals, causing erratic readings or a sensor fault down the line. On a fly-by-wire throttle body, stick to a cleaner explicitly labeled safe for use on electronic throttle bodies and TPS units (most major brands make one), spray it on a rag rather than directly into the assembly, and keep it away from the electrical connector and sensor housing entirely. On a cable-actuated body, a standard throttle body/carb cleaner is fine to spray directly, since there's no sensor to protect — just keep it off rubber boots and gaskets you intend to reuse, since some solvents will swell or dry out rubber over repeated exposure.
In either case, work the valve open by hand (cable-actuated) or have an assistant briefly key the ignition on without starting (electronic, following the manufacturer's procedure — check your model's service manual, since some ECUs need the throttle relearn procedure run afterward) so you can clean behind the valve edge where the worst buildup collects, not just the visible bore surface. A soft brass brush or a folded rag on a pick tool clears the edge without scratching the bore. Once clean, rotate the valve through its full range by hand and confirm it swings freely and returns to idle position under spring tension alone before reassembling anything.
If salt corrosion has already pitted the bore or seized the shaft bushings, cleaning won't restore free movement — that's a wear condition, not a contamination one, and it means a replacement throttle body or a bushing service, not another round of solvent.
Air Intake and the Case for an Aftermarket Flame Arrestor
The flame arrestor sits between the intake track and the throttle body on most PWC engines, doing two jobs at once: filtering intake air and acting as a screen that prevents flame from an intake backfire propagating back into the engine bay — a real safety function, which is why it's a legally required component on many marine engines, not just a filter with a misleading name.
Salt residue and moisture accumulate in the factory flame arrestor screen the same way they do on the throttle bore, and a clogged one restricts airflow, which shows up as flat low-end response or hesitation under load. Pulling it periodically for a rinse in fresh water and inspection is cheap insurance, especially for saltwater use.
Aftermarket flame arrestors and higher-flow air filters are popular upgrades because the factory screen is sized conservatively for noise and emissions compliance, not maximum flow — a more open-flow unit reduces intake restriction and can measurably improve throttle response and top-end breathing, particularly on modified engines already making more power than stock. The catch is that the factory fuel mapping is tuned around the stock intake's airflow characteristics. Add a significantly higher-flow arrestor without adjusting the tune, and the engine runs leaner than intended at the RPM ranges most affected by the change, since more air is now entering for the same fuel delivery. That's a real risk on carbureted or non-adaptive fuel-injected models — lean running raises combustion temperatures and can lead to detonation and long-term engine damage. Models with a wideband oxygen sensor and adaptive fuel control can compensate for some of that shift on their own, but even then, check the arrestor manufacturer's fitment and tuning notes for your specific engine before installing, and verify the ECU is actually adapting properly afterward.