I tried to start my car today. No go.

For those of you familiar with my last post (Bosch Electronic Ignition), I wired according to best advice / appropriate wiring diagrams, replacing my original ignition system with a Bosch electronic system from a 1975 240. The car won't run at all. Any help at all with a logical way to go about diagnosing the problem would be seiously appreciated!!

The car turns over fine. I have newly rebuilt SU's and by the smell of things they are getting (and giving) gas just fine.

There is absolutely no hint of ignition. I put a timing light on the spark plug wire while cranking and got no strobe at all. It appears I don't have any spark.

The system is wired as follows:
black to ground
white to original (B-18) distributor (-) terminal
green/brown to distributor
blue to fuse box off switched 25 amp fuse.
There were two brown wires (one in loom with the white, and one going into the resitor with the blue wire). I took the resitor out and sent both brown wires (via a diode) to the one and only small terminal on my original starter.
All connections are tight and solid. The fuse box has been rebuilt by SWEM.

Now, the system came to me from eBay so I soppose anything is possible. I don't even know where to start to figure out what is wrong.

Any suggestions (or alternatives for electronic ignition with new distributor) much, much appreciated.

Many thanks.
Kai S.

Kai S.

Sounds like your module isn't getting power in the Start position. Verify positive voltage on the blue wire, in both the Run and Start key positions using a test light.

Side note:
(The heavier guage brown wire I'm talking about, is completely separate from the smaller brown wire that is paired with the green wire to the distributor. they just happen to be the same color.)

The Heavy brown wire is to power the coil. It is not connected to the module. It loops inside the harness on mine and comes out next to the white wire to the coil. If your using the original coil, it doesn't get connected.

The Blue wire is what powers the module. In your case, it would be easiest to go the VClassics route. Hook the wire from starter with diode to the blue wire. The line on the diode should go towards the blue wire. USE CAUTION if backwards the engine will crank. Keep the connetion to the fuse panel as well. The fuse panel connection doesn't have power when starting. No power to module, means no spark.

Forget about connecting both ends of the brown wire, get that blue wire some power and try again.

I did have a bad module once, it would only spark once, when i turned the key off. That is why I'm now experimenting with a $16 GM HEI ignition module. So far so good. Much easier to get replacement than going scrapping.

Good luck,

curtis m. white
http://thirdchoice.com

Here's the diagram:
http://www.stanford.edu/~mcduck/bosch.pdf
I ran without shorting the ballast when starting with no problems.