TVS Jupiter with just 4,700 km on odo shuts down on its own at low rpms

If I close the throttle at slow speeds, the engine dies. It does not happen every day or every time.

BHPian IndigoXLGrandDi recently shared this with other enthusiasts:

We have a TVS Jupiter 110 ZX SmartXConnect bought on 07-12-2022. It has run 4700+ Kms.

I am facing a problem with the vehicle as below:

It shuts down on its own at low idle rpm. While traveling if I close the accelerator at a slow speed, the engine shuts down. There is sufficient fuel in the tank. This (shutdown of the engine) does not happen every day or every time.

I tried to troubleshoot by checking the below part randomly. I found traces of water (I think it's water. Correct me if I am wrong). I have removed water (or whatever the liquid) 3 times at an interval of 1000-1200 kms till date. When I removed the liquid, the vehicle ran fine.

The water quantity may be a half to 1 teaspoonful.

What does this part do? What is/are its function(s)?

Some Rust (?) is seen inside this part. The Red Rectangles are marked to show the same.

This is inside the Yellow Colour Metal Cover shown in 1st and 2nd Photos. What does this flap do?

This is the view after the Plastic-Steel-Rubber Part shown in the 4th Photo is removed.

How does the water find its way here? Or is it the ethanol?

Here's what BHPian adrift@life had to say about the matter:

I believe that's the air suction valve and its filter, the secondary air injection system.

The plate you have removed is a reed valve or a non-return valve that allows air from the air filter to the exhaust side and prevents exhaust backflow.

The vacuum on the exhaust side opens the reed valve when you decelerate.

I am technically vague here as to how this works. I need to brush up. But you're scooter wheezing because it's not getting enough air. The water is due to the condensation because of the valve not opening I guess.

More aware members can correct me.

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