HEI/Est Ignition System

Spark

Check for spark at coil wire and at each spark plug wire using a high output spark tester. Check spark plug wire resistance on suspect wires. Resistance should less than 30,000 per wire.

Ignition Coil Power Source

Turn ignition on. Using voltmeter, check voltage between terminal B+ (Red/White wire) and ignition coil ground. Battery voltage should be present.

Ignition Coil Testing

1) Using an ohmmeter, check continuity between B+ terminal and base of ignition coil. See Fig 1 . Reading should be high (infinite or open circuit). If reading is not infinite or open, replace coil.

2) Check continuity between "B+" terminal and "C-" terminal. Reading should be low or zero (continuity). If not, replace coil.

3) Check continuity between "C+" terminal and coil secondary terminal. If reading is infinite (open circuit), replace coil.

Fig 1: Testing Ignition Coil

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Distributor & Ignition System Check

Use circuit wiring diagram and diagnostic flow chart (C-4B) to diagnose and service ignition system. See Fig 2 and Fig 3 .

Fig 2: Ignition System Check (Chart C-4B Circuit Wiring Diagram)

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Fig 3: Ignition System Check (Chart C-4B Flow Chart)

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