Good morning,
I have a good one here that I need help with
My 1990, 964 run fine till I parked it for a few weeks in the garage.
When I tried to use it again, it would not start. It is cranking over fine, has fuel pressure and spark on both distributors.
After some more investigating, we found that the car would start and run with only one of the ignition banks connected. It is running on either the upper or the lower spark system but not on both of them together. If it is started on one or the other spark banks and the one that was disconnected is connected again, the car shuts down.

The coils and the ignition systems have been swapped around and the problem is still the same. So, the ignition portion is working fine just not both together as it is suppose to be.

Any ideas?

Thanks TK