They told me that they don't keep records from past 94 when I called for my key code, but a second time I called they could look up some information which was "achived". To unarchive took them about a week. Don't expect much info. from them on your car. All I got was a list of 3 recalls on the Z, and the dealer that serviced them (no key code). My timing belt was changed at a Nissan dealer and it was not listed. My car is a 91, so we are out of luck.
