__CONFIG _CP_OFF & _WDT_OFF & _PWRTE_ON & _HS_OSC
; timing based on 1.12MHz RC oscillator configuration using 5.1Kohm + 100pf

Hi there,
Your first problem is you've defined a high speed oscillator but have an RC circuit connected instead.

Change your config line to

__CONFIG _CP_OFF & _WDT_OFF & _PWRTE_ON & _RC_OSC
; timing based on 1.12MHz RC oscillator configuration using 5.1Kohm + 100pf

For time critical applications a ceramic resonator or crystal is much more reliable. Dont forget the load capacitors for the crystal!

Tim.