Intermittent no spark (1 Viewer)

[roaddog77]

I have an 86 FJ60 with a DUI distributor in it. Been great for a long time. Recently I’ve had it occasionally not want to start. Starter turns over fine but no spark. Also on occasion the horn won’t work. When this happens everything else works, the fan, lights, guages, radio etc.

When I check with the ignition turned to on I have 12.25 volts or so at the battery connector to the distributor. I’m not sure what I should have at the B+ and C- plugs. Those show no voltage with the ignition on.

I’ve searched on here and can’t find anything quite like this. All the fuses are good. Fusible link seems good. Battery connections are good. Any idea what could be causing it and where to look first? I was thinking the ignition switch at first but not sure that would be the issue if my dizzy is getting voltage. Maybe inside the DUI? Loose ground somewhere?

 

[cruisermatt]

Have you pulled the cap and checked the rotor? The DUI's have plastic screws that hold the rotor in place and can have intermittent issues. The DUI is really a huge downgrade from the OEM Big-cap unit your 60 originally came with

 

[roaddog77]

Have you pulled the cap and checked the rotor? The DUI's have plastic screws that hold the rotor in place and can have intermittent issues. The DUI is really a huge downgrade from the OEM Big-cap unit your 60 originally came with

No I haven’t popped the cap off. Figured I would soon.

The old igniter and distributor were giving me issues. Previous owner desmogged it and left the vacuum port open so a lot of corrosion inside the distributor. Not sure if the signal generator in there or the igniter went out. They’re both hard to find parts so went DUI.

 

[fjc-man]

Might not have anything to do with the distributor, is that the original electrical portion of the ignition switch?

 

[roaddog77]

No I haven’t popped the cap off. Figured I would soon.

The old igniter and distributor were giving me issues. Previous owner desmogged it and left the vacuum port open so a lot of corrosion inside the distributor. Not sure if the signal generator in there or the igniter went out. They’re both hard to find parts so went DUI.

Might not have anything to do with the distributor, is that the original electrical portion of the ignition switch?

Still the original ignition switch. I took the cover off of the steering column. Looked around. With the intermittent horn issue I’m thinking maybe something in the harness or connectors. Haven’t dug too deep yet. Think the switch might be going?

 

[fjc-man]

The internal contacts of the switch are like old school ignition points, they build up resistance to current flow over time. Just imagine the number of times the key has been cycled.