To properly access the data, you should use bracket notation:
var myJSONObject = [];
var id = "1", value = "I'm a value!";
var obj = {};
obj[id] = value;
// ^------- Make sure to use this notation!
myJSONObject.push(obj);
When retrieving a value with a numeric key, remember to use bracket notation as well:
console.log(myJSONObject[0][1]); // or "1"; both will output "I'm a value"
It's important to note that what you're referring to as a "JSON object" is actually a JavaScript array containing one JavaScript object. If you need JSON format (e.g., for server communication), you can do the following:
var jsonString = JSON.stringify(myJSONObject);