Could you just double-check the 3.3v connection? It should be 2nd or 4th from the end of the Arduino connection : http://www.espruino.com/Pixl.js#pinout
You don't actually need the 4k7 resistor now (we use the internal resistor in software) but it won't hurt.
85 is the magic number you get when the sensor has just initialised - which is what you might expect if it wasn't powered all the time.
Espruino is a JavaScript interpreter for low-power Microcontrollers. This site is both a support community for Espruino and a place to share what you are working on.
Could you just double-check the 3.3v connection? It should be 2nd or 4th from the end of the Arduino connection : http://www.espruino.com/Pixl.js#pinout
You don't actually need the 4k7 resistor now (we use the internal resistor in software) but it won't hurt.
85 is the magic number you get when the sensor has just initialised - which is what you might expect if it wasn't powered all the time.