2 things here.

1) You are not specifying Latitude/Longitude values for setView method, which are required.  Lat has a range of -90 to 90, and Long -180 to 180.

2) A zoom level of 3 is so far away for NYC that it is quite possible you wouldn't be able to see overlayed borders of the US states let alone the roads within a particular city.

Try replacing your line of code `var map = L.map('map').setView([988008, 213104], 3);` with this:

`var map = L.map('map').setView([40.715646, -73.99933], 14);`

Use the zoom control if you need to, but you should now be able to see your layer.