Power Surge Event - Now No Spark
 

Hi all,

In an unfortunate circumstance I had a power surge event (12v to starter wasn’t bolted on and hit a heat exchanger). Now I’m chasing down some issues and have no spark.

The “event” popped fuses 7/8 (I think those are them) in the front trunk. Those fuses have since been replaced. I had the CDI tested and it is in working order. I tested the coil it is good. The starter works and seems to want to turn over, I’m just not getting spark. This rebuild also has 0 miles on it and had only 10 minutes of running time before this happened.

I’m trying to get ahead of this but I plan to test the ignition switch next.

Is there anything else I should be looking for/testing that could have failed? Any common failure points?

What year is your car and how did you test the cdi and coil?

1972 911T

I bench tested the coil using a multimeter. Unless there is a specific process of testing a Bosch coil that I was not aware of.

The CDI I had sent to a professional rebuilder who tested it and said it was all in working order. He had rebuilt it for me before i had the event.

Now, it's time to test it in the car, a 5 minute test. Most likely you have a three pin CDI which uses points to trigger a spark.
Just remove the coil wire at the distributor and place it about a 1/4 to 3/8 inches away from the base of the coil.
Then remove the black wire at the distributor input and momentarily ground it which should produce a spark.
Did your "professional rebuilder" help you troubleshoot this?