Hi Ann, Dawn ultra is good with oils so I would use it to clean them. If you can take them off, scrub the dawn where the problem is and then wash. White Brite works well in the wash on fabrics like this also.
Shampoo or Blue Dawn
I have learned the hard way but oil removes oil so use a white cloth and wd40 once the stain is gone use baking soda to dry it up
Try pouring corn starch or baby powder on the stain to absorb the oil..then launder