Used to use an enzyme cleaner in our Lube centers. We called it "Bugs" it did geat, spray it on let it sit over night no more oil, just a nice clean surface.
The enzymes will not work if they come into contact with other cleaners etc. So to get it to work best you need to stay with it and discontinue other cleaners that will "kill" the enzymes. probabl ysame type of stuff. Anything oily or geasy it will eat the oil away.