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I have a 1999 r34 gt rb20de neo auto. been converted to manual using rb20det gearbox and completed the wiring for the inhibitor and speed sensor, reverse light switch, first start it had a check engine light and i did the diagnostic and got the code 56 triple checked it wasnt code 55 anyone have any clue ?

Sorry to revive this topic again Rb20det Gearboxes are caving my head in. So I have Rb25det With a rb20det manny trans. In my C34 auto converted . the speedo Is reading half the speed and i dont know where to start So what ive got is the speedo in the gearbox sends an electric signal to the dash which converts it and whats happening is its only getting half ? so do i need an electric converter. Rb25det electric speed sensors are long ones so they wouldnt work with my rb20det one