Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

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Ignition Coil Circuit





1) Remove distributor cap and disconnect distributor coupler.
2) Measure primary and secondary coil circuit resistances.

Ignition coil resistance at 20°C (68°F)
Primary circuit 0.7 - 0.9 Ohms
Secondary circuit 13 - 18 k Ohms


If check result is not satisfactory, replace distributor.