Hi folks Iam new to the site so plz forgive me. I have a95 Sedan Diville 4.9l. when going through the pcm data there dosent seem to be a PD42 code, this is for calculated octane.It goes to PD39 and than jumps to PD70?? Am I doing something wrong? Also is this obd 1 or obd 11?? Thanks Rich

 

I believe pre 96 is OBD 1

 

OBD2 is 96 and newer, PD 42 is not availible on the 4.9l Deville. It is availible on the 4.6l Deville Concours.