A timing cover leak is an issue that can go either way for your car. It could be a small leak that will cause your car to lose oil over time, or it could be a significant leak that will cause major engine problems. If your timing cover oil leak is not too significant, you might be able to drive your car for a while before it becomes a severe problem. But if you have to drive with a timing cover leak, make sure to check the car's oil level every day. And if the oil level is low, add some more.