Hi,

While I was unscrewing the ignition coils today, I noticed that the fourth 10mm bolt was severely corroded, the first 3 screws had no corrosion at all I removed the screw but you can see what rust was left in pic 1. In the second pic you can see 2 even more severely corroded bolts. The bottom one on the (intake cover?) is completely shot. Would anyone have any idea why there is such bad corrosion just in this area? I can't see evidence of any obvious leaks but I could easily be missing something. Thanks.

 

This is not really uncommon in many places in the world. A lot has to do with the % of moisture in the air. Your coil pack if only one is that way then I would suspect it was not secure properly.

I also DONT see any area that as you described it as being "SHOT". Try pressure washing your engine at least once a year and it will reduce this from happening

If you look at the OPs pictures and understand about surface corrosion of some metals and specifically aluminum having to do with engine and chassis parts it is easy to clean up for the most part and somewhat semi preventative in such by a cleaning of both the chassis and engine bay with simple car wash and water.