Here's a how to save on some code space a long with a marginal increase in speed. Avoid using the AND operator where possible by multiple nesting IF's.

Code:
if (EGT > 300) then
   if (RPM > PumpAdd +10) then
      if  (FlameOut_1=0) then
          FlameOut_1=1 
          gosub opengasoff  'Close Gas Valve
      endif
   endif
endif
Also try to avoid GOTO and GOSUB where possible. Most often, programs which make extensive use of them turn out to be spaghetti code.