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Ignition Control Module

Check ignition coil, ECM/PCM and high-tension lead connections. Check secondary coil winding and high-tension lead resistance. Measure voltage between ground and appropriate ECM/PCM terminals. See ECM/PCM TERMINAL IDENTIFICATION  table. If all measurements are within specification, and misfire still occurs, replace distributor or ignition coil.

ECM/PCM TERMINAL IDENTIFICATION

ECM/PCM Wire Color (1) Closed Throttle Volts WOT Volts
Red/White (3B) Less Than 1 1-2
White (4F) 0 Or 5 2
Yellow/Blue (4G) 0 Or 5 1.5
Brown/Yellow (4N) Less Than 1 .2
Brown (4R) Less Than 1 .2
(1) ECM/PCM terminal number in parentheses. See PIN VOLTAGE/PID VALUE CHARTS article for terminal identification.