WIERD Electrical Problem.....

[Anonymous]

I am real close to starting the crossflow here (I hope!). Today, I hooked up my spark tester and gave the engine a couple quick cranks to check for spark. There was no spark.

I am using a set of used wires that came with the motor. I checked them a few days ago with my multimeter and they were all ok so I figured I would use them for a while. I was missing the wire that goes between the coil and dizzy so I grabbed a new one from Autozoo.

The dizzy is a bosch 2 wire unit from Oz. Just 2 wires (12v) go to the coil and then the dizzy's 2 wires piggyback on the coil.

I am using the US duraspark 12V coil.

I have 11V at the coil when the ignition switch is closed.

So I pull off the cap and rotor along with the wire set to see what is going on. Every last wire is bad now even the new one. I actually had to test some other spark plug wires I had laying around the garage because I thought my meter was broke.

The coil was warm to the touch (not hot) a few minutes after trying to start.

Anyone have any ideas on what is going on here? I posted this here and not on the Oz forum hoping more people would see it.

 

[Bort62]

That is very odd, can you be a little more explicit please?

What was the resistance, before and after?

define "bad"

 

[Anonymous]

Feel real stupid here

Changed battery on meter and now they all check out. Not sure why the meter worked for the spare wire I had in the garage though.... OH well. I thought something was wierd here. Guess I should double check from now on before posting here and looking like a fool.....................

The rest of my question still stands though. I have 11V at the coil but no spark...............

 

[Mercury Mike]

Make sure the 2 wires to the coil from the dizzy aren't switched around. I did that by accident and was kicking myself in the ass because I couldn't get the beast started. =D

 

[Bort62]

Well, if you have >~ 9v at the coil, signal from the reluctor to the module, and power to the module, you will get spark.

So, either - your arent getting a reluctor signal to the module, the module isnt powered, or it is busted.

It's hard to check for reluctor signal without an O-scope (which your average DIY won't have). You might be able to use your meter set on AC and look for soome AC voltage (2.5 or 6 probalby) while cranking between the reluctor leads. Haven't personally tried this.

So make sure all the wires from the distributor to the module are correctly attached and in good condition.

Take your meter and measure for 12v at the module.

If all of this checks out, you most likely have a bad module.


This all assumes that it is hooked up correctly - this is by far the most likely cause of problems.

 

[addo]

Could be a dead module. Typical sign is a single weak orange spark when the power's switched on. You can substitute the GM module but will need shielded twin conductor wire from the pickup spade terminals to the module on heatsink. Or use the pickup to power an MSD.

The other possible is your original oil-filled coil might have drained somewhat through the vent, and now has an internal open circuit.

 

[Bort62]

You don't need to use sheilded wire from the reluctor to the module, the signal is actually pretty strong.

 

[Anonymous]

Well, I am having a duraspark shaft turned down and I am going to put that set up back in the car. The bosch is a better unit in it's stock form but this has convinced me that US ignition system is more practical for me at this time.

 

[Bort62]

Sounds like a good plan.

Altho the bosch unit should work, but I can't give you any specifics without seeing it.