I recently purchased a 1997 Sable with 99k miles that runs good. However, I have noticed that whenever the engine is cold or sits overnight, the ABS light will blink momentarily when I start the car.

Once the car warms up, and I drive to my destination and park, and let it sit for a few hours, when I start the car again, the ABS light does not appear.

The light never appears steady while I drive.

Is this behavior normal, meaning the ABS system checks itself once every 24 hours?

 

Check your ABS connections. Cold metal contracts, and when warmed up it expands and makes good contact.