|Because both my black and titanium keys would fall out of the ignition when driving.
Turns out, I just needed new keys. Turns out my almost never used VALET key was still like new. Turns out that the cut on the valet key is the same as the cut on the black master key, but the lengthwise grooves are what’s different.
So, locksmith cut a new key onto a master blank from the valet key, and now problem solved. Apparently it’s the diamond shaped tip on the end of the key that stops it falling out, and mine were badly worn.
Also, a lot less hassle than replacing the lock and getting it rekeyed to match the rest of the car.