There are a few things you could check out. First, shine a flashlight into the vent at the rear of the passenger side quarter panel. This is where the engine takes in it's air. Look down and see if anything is blocking the drain to allow water out. If this is clogged water may be getting into your intake messing up the compustion process. Also follow the intake plumbing from the pontoon to the air cleaner assembly. If you accidentally torn or loosened somthing when replaceing your header bottle, this could also allow water to get into the engine. Another possible problem could be the boots around your spark plugs and fuel injectors. If they are out of place or damaged, water may be seaping into the engine or plug wells and causing similar problems as water in the intake would. Watch your temperature. Without a heat shield around the muffler, it could be heating up your engine more than it can cool. A hot (but not yet overheated) engine can loose performance, but probably nothing like you described. The throttle shield recall is primarily so the throttle spool doesn't freeze or stick. If your pedal has full movement without any problems, dont worry about it. (Just dont drive below freezing). Jim Reeve '81 DeLorean - #6960 AIM - Ultra2169 http://www.dmcultra.com