IR sensor not detecting light or dark sufaces

Question

I wrote code for the vibrating motors to vibrate when an IR sensor detects a darker surface. I have 4 vibration motors for corresponding 4 IR sensors. My program is not able to read the values from the sensor. In the serial monitor the values that are read from the sensor is a huge non stopping value. None of my IR sensors is detecting the surface. As a result no vibrations are produced. I am using Arduino Pro Mini and my code is:

#include <EEPROM.h>
// pin numbers
const int irLED = 7; // wire connected to transistor/220 ohm resistor (all on same pin)
const int collectors[] = {A0,A1,A2,A3}; // (with pullup resistors)
const int vibrations[] = {3,5,6,9}; // vibration motors

// thresholds for each finger
int detectionThreshold[] = {940,960,970,975};
int whiteThreshold[] = {600,600,600,600};

// timers (in milliseconds)
int lastVibration[] = {0,0,0,0};
const int numFingers = 4;
int readings[] = {1023, 1023, 1023, 1023, 1023, 1023};
boolean vibrating[] = {false, false, false, false};


void blackLoop()
{
  int now = millis();

  // get the current readings
  for(int i = 0; i < numFingers; i++)
  {
    readings[i] = analogRead(collectors[i]);
    Serial.print(readings[i]);
  }

  // vibrate on black, with minimum vibration time
  for(int i = 0; i < numFingers; i++)
  {
    if(readings[i]<=detectionThreshold && readings[i] >= whiteThreshold[i])
    { Serial.print(readings[i]);
      digitalWrite(vibrations[i], HIGH);
      vibrating[i] = true;
      lastVibration[i] = now;
    }
    else // if(now - lastVibration[i] > vibrationDuration)
    {
      digitalWrite(vibrations[i], LOW);
      vibrating[i] = false;
    }
  }
}
void setup() 
{
  // put your setup code here, to run once:
  for(int i=0; i<numFingers; i++) 
  {
    digitalWrite(collectors[i], HIGH);  // set pullup 
    pinMode(vibrations[i], OUTPUT);
  }

   pinMode(irLED, OUTPUT);
   digitalWrite(irLED, HIGH);
   Serial.begin(9600);
   Serial.println("my sketch has started");

}

void loop()
{
  // put your main code here, to run repeatedly:
  blackLoop();

}