How do I remove the connecting rod so I can take the popup out to check for sluggish drainage ?

Is your sink clogged or just sluggish, you can do other things before you remove the stoper, 1st fill the sink with water and use a plunger, second take 1/2 cup baking soda mixed with 1/2 cup of salt put it in sink drain then poor 1 cup of white vinegar, leave it over night, in the morning put some very hot water in the drain, if still not clear then go under the sink remove the trap clean and install, to remove the pop see the pictures it may help you, Good Luck.
John

Loosen nut RP6132, pull lift rod back 1/2", take out pop up.

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If the stopper won't pull up then the installer tied it down. To free the stopper, push down on the knob raising the stopper to the drain position. Now go underneith the lavatory and locate a knured nut with a rod sticking out of it. Take a pair of pliers and free the nut just enough for it to turn by hand. STOP! Now hand loosen the nut enough so the nut and rod just begains to clear. STOP!
Now GENTLY, while you're pulling up on the stopper pull the nut and rod out SLOWLY and STOP when the stopper clears enough to remove. CAREFUL! Don't let it pull all the way out. Now tighten the nut by hand and snug it up with a pair of pliers. You may now just drop the stopper in and it will continue to ride on top of the rod so if you ever have to remove it you can.
Hope this helps . Tom

First, remove stopper and see inside. There may be body hair wrapped around the stopper. If not, proceed with removing pop-up assembly as suggested in other posts.