Sure sounds like a fuel supply issue to me, but kinda baffled by your "throttle back" description for remedy.

I would pull the fuel line downstream of pump and filter, but upstream of card and observe flow.

If that seems normal, I would pull fuel bowl on bottom of carb and check float is not sticking.

While there check for dirt particles.

When it starts to die if possible, shoot some carb cleaner directly in carb. If accelerates, then definitely fuel supply issue, and carb clean/kit would be my next move.

Hope it helps

Replace the "ignition delay module". Common problem with these. This module is responsible for keeping the engine running for a moment after the key is turned off to burn up any unused fuel. Less than $20.00 at your dealer. Well it used to be less than $20.00.

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