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

When installing a service replacement ECM, the use of incorrect MEM-CAL installation procedures may cause the ECM to fail before it can be installed in the vehicle. This condition may appear as if the ECM were defective when it was shipped to the dealership when, in fact, it was damaged while being installed. In addition, this condition may also occur when installing as "updated" service into the vehicle's original equipment ECM. Excessive vertical force may be generated in two ways:

• 1) Incorrect MEM-CAL installation procedure.
• 2) Interference between MEM-CAL and cover.