Lg french door refrigerator water leak underneath, when you use water in the door you hear a hissing sound.

Most likely you have a clogged defrost drain.

Sounds like you have to have a leak in the water line somewhere. The water line goes to the top hinge in the door, so the water has to come from somewhere below that point or it would be collecting inside the door and leak out the front. A leak would prevent water from getting to the ice maker, or a leak at the valve could have this effect as well. Check the water valve that gets a call to send water to the ice maker.

Could be water dripping on the heater when defrosting

When you took the i/m out, the motor has put the door out of synch

LG LFX23961ST Support Manuals Warranty More LG

I just used the link above to get the Manuals on your LG. On page 31, they did the following CYA statements...

The defrost timer will click when the automatic defrost cycle begins and ends. The thermostat control (or refrigerator control, depending on the model) will also click when cycling on and off. Rattling noises may come from the flow of refrigerant, the water line, or items stored on top of the refrigerator .
Your refrigerator is designed to run more efficiently to keep your food items at the desired temperature. The high efficiency compressor may cause your new refrigerator to run longer than your old one, and
you may hear a pulsating or high-pitched sound.
You may hear the evaporator fan motor circulating the air through the refrigerator and freezer compartments.
As each cycle ends, you may hear a gurgling sound due to the refrigerant flowing in your refrigerator.
Contraction and expansion of the inside walls may cause a popping noise.
Water dripping on the defrost heater during a defrost cycle may cause a sizzling sound.
You may hear air being forced over the condenser by the condenser fan.
You may hear water running into the drain pan during the defrost cycle.

I bolded the statement. Sounds like you are going to have to get used to the sound.

Semper Fi,
Z

Make sure your ic maker is empty. On the bottom of the ice maker is a small button. Watch the plastic fill tube and hold the botton in. Let the ice maker cycle anmd see if the water over shhoots rne ice maker. If it does, trim 1/8 of an inch off of the tube with a raxor knife on an angle = / this should take care of your problem.

Yes. Every 12-14 hours your refrigerator goes through an automatic defrost to clear the ice from the evaporator. The hissing sound your hearing is the water dripping on to a burning hot element.

No Worries.

I poked a hole in the freezer with my knife while trying to defrost it. Now it is making a constant hissing sound. what should I do? is this dangerous?

under the compressor there will be rubber bushes which would have got damaged so change the rubber bush and ur problem may get solved

The only thing I can think of that you may be hearing would be if the compressor has a problem. If you notice cooling performance decrease or it stops cooling, I believe you will find the compressor has bad internal valves. It will probably take a technician to properly diagnose this and if the compressor has this problem the only answer is to replace the compressor.
I hope this helps, supertechks