i had a similar problem, was a stuck solenoid in my case.... all i had to do was take apart my dash and clean it with electronics cleaner with the car off (looked like the previous owner had poured coffee all over the dash every day of their lives and only wiped off the noticeable stuff). i can now hear a slight *tick* coming from the dash when i squeeze the shifter when going into/out of park (the solenoid charging up)