Suburban 1/2 Ton 4WD V8-305 5.0L (1986)
Ignition Coil: Testing and Inspection
IGNITION COIL TEST
Connect ohmmeter. Test 1
Reading shouid be zero. or nearly zero. If not. replace coil.
Connect ohmmeter both ways. Test 2. Use high scale. Replace coil only if both readings are infinite.
If coil is good, go down to Pickup coil test.
PICKUP COIL TEST
On all distributors,including distributors with hall effect switch, remove rotor and pickup coil leads from module.
Connect ohmmeter test 1 and then test 2.
If vacuum unit is used, connect vacuum source to vacuum unit.Replace unit if inoperative.Observe ohmmeter throughout vacuum range; flex leads by
hand without vacuum to check for intermittent opens.
Test 1- should read infinite at all times.
Test 2- should read steady at one value within 500-1500 ohm range.
NOTE:Ohmmeter may deflect if operating vacuum unit causes teeth to align.This is not a defect.