hesitation

1999 Subaru Legacy Outback 2.5 295,000 miles symptoms: for about 3 or 4 years, my car does two things I cannot figure out. 1. when cruising up a particular long hill, medium grade, it lurches just slightly, but ongoing. 2. when traveling I'd say 25 mph or slower, if I punch it, it bogs...

When I installed my audio system 3 years ago I also upgraded the main power and grounds under the hood. Alt+ to Batt+ Batt- to drivers strut tower. This really should be protected with a fuse but the thick casing on welding cable, wrapped in split loom tubing and being inside of the factory...