Toyota Repair: transmission, dish soap, toyota corolla

Question
toyota corolla le 2001 auto trans 90,000 mi my daughter spilled a can of soda onto gear shift of car since theat time when you put car in drive we have to be very exact as to where to place shidt if i move shift slightly while remaining in drive the car revs but doesnt move . a slight movement back to the "right spot" and the car is fine. my mechanic says the transmission is fine . how can i correct this problem? thank you for your time

Answer
The sugar in the soft drink wiil cause the shift interlock mechanism to stick, remove the upper part of the shift console, the best way to dissolve the sugar is to fill a spray bottle with dish soap and warm water and spray all the moving parts you can get to while moving the shifter, eventually the soap will get rid of the sugar and things should be back to normal.