Uncaught Error: Syntax error, unrecognized expression

Uncaught Error: Syntax error, unrecognized expression

Hello there!
For last two day's I'm trying to figure out what is causing the syntax error and would appreciate any help.
  1. $("[name='Item.Index']").each(function () {
                    var index = $(this).val();
                    console.log("index: " + index); //index value is 0
                    console.log($("[name='EI[0].ItemType']").val()); //outputs correct value
                    console.log($("[id='EI_0__ItemType']").val()); //outputs correct value
                    var t = "\"[id='EI_" + index + "__ItemType']\"";
                    console.log("t: " + t);  //output is t: "[id='EI_0__ItemType']"
                    console.log($(t).val());
  2. });
The last line console.log($(t).val()); is giving an error:

Uncaught Error: Syntax error, unrecognized expression: "[id='EI_0__ItemType']"
    at Function.Sizzle.error (jquery-3.5.1.js:1677)
    at Sizzle.tokenize (jquery-3.5.1.js:2377)
    at Sizzle.select (jquery-3.5.1.js:2838)
    at Function.Sizzle [as find] (jquery-3.5.1.js:894)
    at jQuery.fn.init.find (jquery-3.5.1.js:3095)
    at new jQuery.fn.init (jquery-3.5.1.js:3205)
    at jQuery (jquery-3.5.1.js:157)
    at HTMLInputElement.<anonymous> (Create:381)
    at Function.each (jquery-3.5.1.js:381)
    at jQuery.fn.init.each (jquery-3.5.1.js:203)


Any clues?

Joe