So I was sold a 1990 n/a rx7 from a buddy who was having some money issues.
It has a
+ borla exhaust system
+ 18k miles on the rebuilt ported engine (new atkin housing/seals)
+ ported intake manifold
+ turbo model fuel injectors
+ high flow fuel pump
+ aluminum flywheel with pressure plate
+ godspeed radiator

He drove up to my other friend's house and it started idling weird, the pop up motors weren't working and it killed itself while driving. No problem, I have a shop to work on it. It's sold to me. Boom. Days later We are evacuated from my neighborhood due to flooding and tried calling tow agency but they wouldn't be available until it was too late. The car was flooded up to the battery.

I have pulled all the interior out and am now just waiting for a new battery to be put in and for the wiring to completely dry. What I do know if the engine is safe, no water entered it and thankfully nothing like twigs/leaves got into it.

Otherwise my questions are what needs to be replaced? Could it be possible for the wiring harness to be alright or just rip it out and replace it regardless? The dash electronics will have to be replaced but what electrical wiring should I watch for in the engine bay?

 

you will need to most likely get another ECU.
The engine should be drained of oil and flushed/replaced.
I would also think about pulling the plugs and shooting massive amounts of oil into the housings and rotating the engine (by hand) to expel any water that May have gotten into the internals.
I'd inspect the exhaust and turbo( let the exhaust dry out..somehow.)
Basically it is a guess as to how far the water damaged everything but going through the connections and replacing the electronics would be beneficial to getting the car back to operational.

 

Before you try to start the car follow the recommendations given above, take the ECU out and get it completely dry. You might be able to save it. I had the same situation with a previous car and the ECU did not suffer any damage.

 

Thanks for the advice! I'll get working on pulling the engine/fluids soon and ecu out this weekend and will let you know if something else goes wrong!

 

obviously you do not need to worry about the coolant system.
Unless the water got into the overflow,then just take out the "crap" and fill with 50/50 coolant to the full line.

 

The other issue is all the wiring. Once water gets to the connections, the copper starts to corrode/oxidize. You also might need to drain the fuel tank. I bet water entered through the vent.