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

(Some people have issue connecting. LEMON is investigating. For now, use Firefox or change your DNS server)

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JB6 - Verify Scope Pattern 5

Spark Plug Firing Voltage Pattern:

- Is there consistently low spark plug firing voltage or sloping spark line in one or more cylinders?

YES -- Fouled spark plug(s). Narrow spark plug gap(s). Spark plug wire(s) grounding on engine. INSPECT spark plugs and wires for damage.

NO -- Ignition Secondary functioning properly. Go to Pinpoint Test Step HD8 for fuel injector and pressure test. HD8 - Check Resistance of Injector(s) and Harness