What needs to be checked for a submerged donor?

[DodgyTim]

My donor is a 2006 clubsport (CS9). I think this is a uniquely Australian build, seems to be STI springs, dampers and gearshift but not much else over stock WRX. Hubs are 5x100 and gearbox is 5 speed.
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It was written off (never to be road registered again) due to water damage …it floods a lot here.
Buying it from an auction you don’t get a lot of info about what happened, but I’d say it didn’t get fully submerged, because all the electrics work! I mean everything, including windows, doors etc. The gauges look pristine and the stereo works fine.
I have recurring engine codes P2440 and P1410 (both secondary air, not a big problem).
So far I’ve drained and changed all the obvious fluids, brake, clutch, power steer, engine, gearbox and diff.

Is there anything I’m missing?
I’m going to do some track days with the car whilst waiting the YEAR until my 818R kit arrives and don’t want to damage anything further because its got water in it or have it corrode out because I didn’t dry it out.
Cheers

[StatGSR]

Well if you started the engine and it works, you have pretty much passed the scary part. Besides doing an exploratory rebuild, I'm not sure what else you need to worry about.

[DodgyTim]

Engine seems fine, the whole car drives quite nicely. It isn't overly grunty, but it appears to be stock, even the exhaust is unmolested

[Wayne Presley]

It seems that the only problem is the water seems to have washed the steering wheel to the wrong side...

[Xusia]

Wayne beat me to it. I was going to say:
Dude... The steering wheel is on the wrong side. I'd check that first!

But on a serious note, I'm no automotive expert, but electronics I know fairly well. If they work, they work. I wouldn't worry too much about them (stereo's are usually pretty sensitive because they have amps, which contain capacitors, blah blah blah - bottom line is if it still works, you should be good!). I'd wash the seats real good to prevent mildew. If you plan to use the car during the next year, you might consider ripping the carpet up to ensure you don't have a nice mold colony or mildew growing.

[DodgyTim]

In 1998, archaeologists found a well-preserved track leading to a Roman quarry near Swindon, England. The grooves in the road on the left side (viewed facing down the track away from the quarry) were much deeper than those on the right side. These grooves suggest that the Romans drove on the left, since carts would exit the quarry heavily loaded, and enter it empty.

This confirms driving on the left is the correct side.....

[Xusia]

That only proves the Roman's were nuts - which we already knew! LOL :)

[tirod]

Mechanically, you did the obvious, change the fluids. What you got out of that was the direct observation of what kind and how much water.

If the electrics are working, so much the better. That is the real long term issue, because water can wick into the wiring at every break in the insulation, and it basically has to bake out. As it does, it corrodes the wiring, which increases the voltage drop. That messes up sensor circuits running 0-5VDC, which is what the computer uses to work.

A worst case scenario would be having a car where the windows and door locks slowly stop working, or a crank or cam sensor being repeatedly replaced in error because the wiring was the issue. And yes, I no longer drive that car. It's just too much hassle.

Considering the huge amount of wiring in the donor Subaru harness, it's a good time to consider options, like a multiplexing CAN bus system.

[Mechie3]

Sometimes they total submerged cars because mold can develop in the fabrics, carpet, and door skins.

If the romans drove on the left, and the Romans are no longer around, clearly, they were doing it wrong. :D

[longislandwrx]

Yeah, as long as you didn't see any water in the pan, I think you are good. If it was salt water, it would be a different story. The only other things I would do is pull the valve covers off to make sure there's no water sitting in the low spots, Take the cover off the ecu and make sure there's no condensation trapped in there, and drain the fuel tank to make sure there's not water sitting in there. then let it run for a few hours to dry it all out and call it a day.

pull the seats out too if you plan on using them and set them out in the sun so they are perfectly dry

[RM1SepEx]

I'd disassemble and clean/refurbish the mechanicals
I'd consider replacing electronic parts, and wiring if they were submurged you can expect long term dendritic growth across the circuits and wires causing long term gremlins.
upholstery items can be flushed, cleaned properly dried to avoid long term mold related issues

[DodgyTim]

Yep, I think the majority of the problems will be wiring. Indivudual electric/electronic bits won't be too much of a worry to replace. I'm interested to see what the custom harness will cost, both for reliability and weight savings!
Thanks for all the input