164 Auto Trans problem

["Emerson" <gre1@domain.elided>]

My 91 164L with 52,000 miles on the clock has always shifted well.  The 
other day I parked the car and when I went back, after about 1/2 hour, I had
no parking lock and I was unable to select any gears.  The cable seems to be
working and it was fine when I parked it.  I had it towed to the shop and
they will be looking at it but I was hoping someone out there may be able to
offer some ideas.  It was shifting great just before parking but I can't be
sure about the parking lock since I always set the brake before putting the
shift into park.  The one thing it does do is when you select park you can
hear the faint sound of the paking lock attempting to set.  Like shifting a
car into park while on the roll.

Thanks in advance,
Glenn

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