You may have a different problem chuck but the Pfc needs power for 1-2sec after the engine is turned off so it saves its state into NVRAM.
I had this problem with my R32 as it wasn't wired up correctly after I did a engine change.
With the skyline when you turn off the engine,1-2 sec later you can hear the relay switching.
http://paulr33.skylinesaustralia.com...rfc-faq.htm#56

I have fried my PowerFC. Is it fixable?
http://paulr33.skylinesaustralia.com...rfc-faq.htm#65