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ECM/Mem-Cal - 1986-91 Models With Mem-Cal: Notes

NOTE: To prevent damage to ECM, ignition must be off before disconnecting or reconnecting any ECM power source (i.e.; battery, ECM connectors, ECM fuse, jumper cables, etc.).
NOTE: The following steps are courtesy of General Motors Technical Service Bulletin No. T-91-95, June, 1991 & Technical Service Bulletin No. 91-6E-18, June, 1991.