I am curious if a 2002 Grand Prix will interchange with a 2006 Grand Prix
Well, I would need more information what exactly you are trying to interchange? in 2004 Pontiac grand prix obviously upgraded to a new body style, and upgraded to a new class OBD2 System, programming is completely different. The old engine ( 3800 serries 2 ), was upgraded to a 3800 Serries 3, which includes a few new parts, but in general theory IS the same block with a number of differences ( Drive by wire Throttle Body, Gen 5 super charger, new forged connecting rods, pistons, pins, new throttle body, new MAF, etc ). You may find a few support websites where they show things that are interchangeable. What are you looking to change over?
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