strip or not

Maurizio,

I tried to read your list of Q & A's but there are just too many and most involved "black" granite.

I have a Shivakashi (beige, gray, burgundy, flecks of black) stone about 3 yrs. old.  I wanted to use a Stain Defense product on

it as oil has managed to stain it in some spots.  But I was told to strip it first to  get off anything the installers put on it.

They left me with a can of spray 3 in 1 Cleaner/Polisher/Protector which I am supposed to apply a couple of times a year.  THis stuff obviously doesn't protect otherwise the oil wouldn't have seeped in.  I am worried about stripping  the granite, don't want to ruin it.  If I must strip it what do I use. Will stripping get the oil out, if not, how do I.  I tried peroxide w/flour and when that didn't work, I tried plaster.  THat help a little but if I don't get it out before sealing, the oil stain will be sealed in forever.

Thanks for your help

Karen