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Ignition Coil: Testing and Inspection

NOTICE: Cold and Hot in the following sentences express the temperature of the coils themselves.
Cold is from - 10°C (14°F) to 50°C (122°F) and
"Hot" is from 50°C (122°F) to 100°C (212°F).


1. DISCONNECT HIGH-TENSION CORDS FROM IGNITION COILS
(See step 2 in high-tension cords inspection)





2. DISCONNECT IGNITION COIL CONNECTORS
3. INSPECT PRIMARY COIL RESISTANCE
- Using an ohmmeter. measure the resistance between the positive (+) and negative (-) terminals.

Primary coil resistance:
Cold: 0.70 - 0.94 ohms
Hot: 0.85 - 1.10 ohms.


- If the resistance is not as specified, replace the ignition coil.





4. INSPECT SECONDARY COIL RESISTANCE
- Using an ohmmeter, measure the resistance between the positive (+) and high-tension terminal.

Secondary coil resistance:
Cold: 10.8 - 14.9 K ohms
Hot: 13.1 - 17.5 K ohms


- If the resistance is not as specified. replace the ignition coil.
5. RECONNECT IGNITION COIL CONNECTORS
6. RECONNECT HIGH-TENSION CORDS TO IGNITION COILS