There's a car two states over from me on FB Marketplace, an S12 200SX. Beautiful car with the original 2.0l engine.

Owner claims that it has a "bad computer" so I'm here asking for some electrical info on the S12:

1. What is the main symptoms of a bad computer that would cause a "no start" condition? will the fuel pump still run? will the distributor spark?
2. On the off chance this is a misdiagnosis, what would stop spark besides the distributor/coil. Are there any separate crank/cam sensors that trigger it?
3. Where is the computer on an '86, what years will interchange and is eBay the best source for a good working one?

For what it's worth I'm somewhat familiar with Nissans in general, just not the 240SX platform. I have a gen 1 Xterra, used to own a Z32 300ZX and am restoring a 280ZX turbo. I plan to "roadkill" this car and have a friend within driving distance who will check it out for me, I'm doing this research with the express purpose of figuring out if this car can be fixed without access to a garage.