Ultrasonic HC-SR04 outputs incorrect dist value

connect pin Vcc to 5V and try again.

Hint: Some use a voltage divider for the Echo pin and some don't, check this Google search

used code

/* ESP8266 */
var sensor = require("HC-SR04").connect(NodeMCU.D1,NodeMCU.D2,function(dist) {
        console.log(dist+" cm away");
});


/* PICO 
var sensor = require("HC-SR04").connect(B3,B4,function(dist) {
        console.log(dist+" cm away");
});
*/
setInterval(function() {
        sensor.trigger(); // send pulse
}, 500);

distance HC-SR04 to

• room ceiling 168.57866655316 cm
  
• hand on top 10.12233265659 cm