I have a 1991 Volvo wagon with an automatic transmission. If the car sits for more then a few hours, it is very hard to get the car out of park. To get the car out of park, I need to shake the shifter and press the shift lock button several times. Once the car shifts out of park the first time, I can stop the car and restart it shiftout the problem repeating, unless the car sits for a few hours. Any ideas?