Congratulations on your discovery that a SAAB interior smells like crayons. You now have a conversation starter for your next party.
It is not your imagination; SAAB interiors smell like crayons.
I have read, but never smelled to be sure, that 2003 and newer SAABs don't smell like crayons. I'm guessing many people reading this post searched for "SAAB" and "crayons" because they have recently been inside a SAAB and were wondering why it smelled that way and if that SAAB was the only one with the crayon smell.
I can't smell the crayons in my SAAB 9-5 anymore. I ask everyone who rides with me if they can smell crayons and they all say the smell is still there. I've just become accustomed to it.
I figured it was a leather treatment that CarMax (where I purchased my SAAB 9-5) happened to use. My other thought was that the previous owner had children and some crayons were hidden down a crack somewhere... melting. It took a search of Facebook to find a group called "my Saab smells like crayons" before I realized that this is a normal feature of SAABs and not something done by the car dealership.
I don't have any real information about what causes the smell, but one message board post I read said it was the insulation under the carpet that smells like crayons. They went on to say that the type of insulation was changed in 2003, causing SAABs to lose the crayon smell. Sounds reasonable to me.