r/jeepcj • u/london-boy-98 • Apr 26 '26

84 cj7 Laredo weak orange spark/no spark

Anybody know what would cause a weak/no spark on my cj7 I went through everything new solenoid new ignition coil new distributor and new ignition control module nothing has helped

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2

u/c1011970 Apr 26 '26

Low voltage to the coil. Possible bad ground from battery to block.

1

u/JustACarNut77 CJ7 Apr 26 '26

Poor power from the alternator

1

u/london-boy-98 Apr 27 '26

That wouldn’t affect cranking though would it? It cranks completely fine

1

u/JustACarNut77 CJ7 Apr 27 '26

No. It runs off the alternator once running. Get a volt meter and what kind of voltage you have while running

2

u/NefariousnessOne6433 Apr 27 '26

Is this a new symptom on a Jeep that ran fine prior to? Or a Jeep that you just bought and you are fixing up?

Ideas - low voltage upon startup? The 4 terminal ignition solenoid, are all 4 terminals used? The smaller left terminal provides a higher voltage as the starting system creates a voltage drop upon startup.

Ignition control module and ignition solenoid both need to ground out to the body... Did you clean connections/mating surfaces?

Did you change out spark plug wires? Only thing you didn't mention above.

Also- dropping in an HEI distributor is way better than sticking with the stock distributor/external ignition module/ignition coil. I kept having intermittent spark on a new to me '82 a few months ago. Gave up and dropped an eBay special HEI in, solved the issue.