A brake pedal interlock to prevent shifting out of park unless the brake pedal is pushed. Since the problem is intermittent, we know it's not caused by a blown brake light fuse. The common suspect would be a misadjusted brake light switch, or the switch has pitted contacts. Try pressing the pedal further, and try releasing and pressing it multiple times. I would replace the interlock solenoid which the intrusions in the diagrams below will help show you how to do both column and floor shifters. Check out the diagrams (Below). Please let us know what happens.
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Tuesday, October 8th, 2013 AT 9:42 AM