. Check all under hood and under dash fuses with a test light or multimeter. Especially test the ACG (ALT) (S) fuse in the under dash fuse box. It's likely in the upper right-hand portion of the fuse box. If it's missing, replace it.
. Clean the main ECM ground, located on the thermostat housing. It likely has 3 wires going to a brass connector.
. Check the ignition switch for wear, pitting, or melting.
. If the Check Engine Light consistently comes on for 2 seconds and then goes out, when the ignition switch is turned to ON (Position II), then the problem is likely with the distributor. Usually, replacing the Ignition Control Module (ICM) and coil solves the problem. Be sure to apply silicone heat transfer grease to the back of the new ICM.