LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Jeep >> 1990 >> Wrangler S >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - System/Component Tests - CARBURETED >> Ignition Coil Test >> Ignition Coil Output Test
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Ignition Coil Output Test

  1. Connect an oscilloscope to ignition coil. Refer to test equipment manufacturer's instructions. Start engine and observe secondary ignition voltage.
    CAUTION: DO NOT remove wires from spark plugs for cylinders No. 1 or 5 when performing next test because pick-up coil may be damaged.
    CAUTION: DO NOT operate engine with spark plug disconnected for more than 30 seconds because catalytic converter may be damaged.
  2. Remove one spark plug wire from distributor cap. Observe voltage applied to disconnected spark plug wire on oscilloscope. This voltage, referred to as open circuit output voltage, should be 24,000 volts minimum with engine speed of 1000 RPM.
scientia non olet · About LEMON Manuals