I have a '91 740 sedan with less than 50K (miles). The ABS light comes on every now and then especially when the car is first started, usually re-starting solves the problem but not always.
I've cleaned the sensors at both front wheels, but have not cleaned the pulse wheels. The connections for each wheel sensor have been cleaned and lubed with a small amount of copper-grease. I've also recently changed the battery and had the charging system checked.

Question(s): Should the sensors be cleaned with "something" other than a soft brush? Should they be de-magnetized? What is the best method to clear the pulse wheels?

Thank you in advance, Ron