>   movwf  Throttle
>  movlw D'55'
>   addwf  Throttle,W
>    btfss   status, 0

> FALSE   goto   false_10
> TRUE     bsf     PORTB,0
> GOTO    continue_10
> false_10    bcf   PORTB,0
> continue_10  return

Have you tried a loop with LEDs not involving the A/D ? Perhaps
single-stepping the loop with a pushbutton ? It seems there's
something else going on that may have been overlooked or
assumed. Is there anything else that PortB is being used for ?
For example, does it have floating inputs or anything like that
which would affect what you see. Could it be possible that the
LED=carry properly but gets turned off quickly after it's set so
you only think it didn't work ?

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