flow meter count

Newbie here, so sorry if this is in the wrong place!

having a few issues with reading a pulsed flow meter through digital pin 4. Pins 2,3,7 & 10 are all functioning.

Is this because pin 4 works in a different way?

Code below:

#include <EnableInterrupt.h>
#include <TimerOne.h>
// Pulse Count x5 on Leonardo
// Variables
const int ledPin              = 13;        
const byte pulsePin2          = 2;
const byte pulsePin3          = 3; 
const byte pulsePin4          = 7; 
const byte pulsePin7          = 10;  
const byte pulsePin10          = 4; // choose pin    
volatile long pulsePinCounter1= 0;
volatile long pulsePinCounter2= 0; 
volatile long pulsePinCounter3= 0; 
volatile long pulsePinCounter4= 0;  
volatile long pulsePinCounter5= 0; // new
const byte pulsePin4          = 7;
const byte pulsePin7          = 10; 
const byte pulsePin10          = 4;

I assume that those variable names make sense to you but they could, at the very least, be confusing

Which Arduino board are you using ?

Please look at Read this before posting a programming question and follow the instructions about how to post code

Thanks for the quick reply. Edited the original post!

Yes completely right the varibale names made sense before I started changing the order of pins!

Using a Leonardo.

Thanks for adding the code tags

Variable names generally make more sense if they give an indication of their function rather than being generic

Is this because pin 4 works in a different way?
Using a Leonardo.

Pin 4 on the Leonardo does not support either an external or pinchange interrupt.

From the "Read Me" section of the library EnableInterrupt.h

On the Leonardo there are 7 pin change interrupt pins in addition
to the 5 external interrupt pins. See PIN BESTIARY below for the pin numbers and
other details.

Arduino Leonardo

Interrupt Type Pins
External 0-3 and 7
Pin Change 8-11 and SCK, MOSI, MISO

Perfect. Thanks very much Cattledog