Control Module & Stator Check
- Refer to step 1) of Coil Primary Circuit Check. If modified plug sparked, but engine would not run, substitute any known good distributor (not limited to 4-cylinder). Attach distributor connector to control module harness connector. Run 15" ground wire from vacuum unit screw to engine ground. Spin drive gear and check for sparks.
- If sparks occur, reconnect original distributor to check if it is damaged. Repeat tests to check for sparks. If sparks now occur, see INTERMITTENT OPERATION CHECK . If no sparks occur, replace distributor stator assembly.
- If no sparks occurred when gear of good distributor was spun, disconnect 3-wire distributor connector and 4-wire control module connector. Check harness wires as shown in steps 4) through 8).
- Turn ignition switch "OFF". Connect ohmmeter leads to ends of each wire, one at a time. Wire mating with control module black wire (terminal 8) grounds the distributor. Wires mating with control module orange wire (terminal 3) and purple wire (terminal 7) signal control module as to when coil primary circuit should be shut off and on. Continuity should exist at each wire.
- Then connect ohmmeter leads to harness wires mating with orange and purple wires of control module. There should be no continuity between these 2 wires.
- Then connect one ohmmeter lead to ground and touch other lead in turn to wires mating orange and purple control module wires. An open condition should exist.
- If harness checks OK, reconnect distributor connector and substitute a known good control module and repeat system tests. If no spark occurs, see INTERMITTENT OPERATION CHECK . If sparks occur, reconnect original control module and retest. If no sparks occur now, replace control module.
- If harness proved defective in step 4) through step 6), repair wires or connectors as necessary and retest for spark at modified plug.