the title says it all, but here's more detail.

I have a 99.5 b5, the hinge broke on my fob but the blade was fine. I ordered a fob ebay style w/ matching fcc numbers. Put the blade in the new fob. Key works great mechanically. Car starts.

I only have the one key, is it possible to program this key?

Please no, coulda shoulda woulda, is it possible to program this key? (I've tried they key synching described in the owners manual and it didn't work).

even more detail, I actually ordered an entire fob with blank but the dealership and the only local locksmith with the gear to do it, wouldn't, when i let out that i got the thing off ebay. So, I yanked the blank blade from the new fob and stuck mine in there and my car started right up.

My vin is 99.5 split but surprisingly this must mean the fob isn't immobilizer enabled.

Thanks in advance, cheers!