In the distant past, when untreated rocker panels collected dirt and moisture, it resulted in massive steel cancer. We could have rust in the door bottoms, behind the bracing under the hood or trunk, and any place where panels were crimped/welded together. Nowadays, we are just advised to keep the drain holes unobstructed, in the rocker panels, as well as the door bottoms, as steel bodies have zinc galvanizing in the rust-prone areas.
The NSX lower body is AH-PO aluminum, which is corrosion resistant, so we can reasonably assume that it will take some neglect to spawn an outbreak of corrosion. But, just as in a steel-bodied automobile, when you do your major salt removal washing, it might just be advisable to pay attention to semi-sealed areas where dirt and salty moisture can get in, but not easily back out. These areas are behind the side sill panel, the fender liners, and the front and rear bumper assemblies. I have not researched nor tried to wash these areas myself as of yet, and it may require some contortions or partial disassembly. You have to decide if it is worth the trouble. Unless you have substantial deposits of salt, it may be more of a 'feel good' situation than anything else, that your 'out of sight' areas are as clean as the ones everyone sees. Personally, I am the kind of guy who cleans the dust out of unseen areas that I expose while working on an electrical problem, so I understand the 'feel good' aspect of hidden cleanliness. Yes,I would definitely advise massive amounts of moderate to high (being very careful) pressure water under the car, and not just in the spring, but above freezing temperatures until dry, of course. There is also an area at the front sides of the drain channel near the trunk lid hinge area that is prone to collect trash, and could harbor salt.
Happy cleaning,
Bill
) can explain me the advantage of aluminium vs steel in salt protection. Additionally, does water/wet streets make the salt action worse than on the car than dry pavement?
