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1992-1999Series I L27 (1992-1994 SE,SLE, SSE) & Series II L36 (1995-1999 SE, SSE, SLE) and
common problems for the Series I and II L67 (all supercharged models 92-99) Including Olds 88's, Olds LSS's and Buick Lesabres
Please use General Chat for non-mechanical issues, and Performance and Brainstorming for improvements.
I imagine you could do it at either place. The data line goes all of the way back to the DLC. Although it appears you would have to disconnect the harness at the EBCTM in order to check it.