2000 Grand Prix Keyless Entry Problems

I just got a used 2000 Grand Prix, V-8 with 102,000 miles. I have just recently developed remote entry problems. For some reason the remote just works when it wants to. I'd rather not spend tons of money to have Pontiac work on it for 5 seconds. I was wondering if any one had any ideas or if you could point me in the direction of the correct forum. I have tried like resynching the remote with the car and have also tried a new battery... to no avail. Help Please!