94 GM - clock won't keep time

The clock on my 94 Grand Marquise loses time randomly when the ignition is shut off. I can reset the clock when the engine is running and it does fine. The ignition could be off for only a few minutes, but the clock setting will be hours off when I start the car again. Anyone know what the problem is and how to fix it?

Thanks in advance for any assistance.

degorio

How old is your battery? Are the connections to the battery clean and secure? Check the power connections to the clock.