Todd, I realize we have different engines, but some things that come to mind. As your problems usually show when cold, I would suspect emissions problems, Charcoal canister, Purge valve, evap tank, return lines, etc., the parameters change with temp and conditions. Also having seen and referenced your site I assume you're a pretty thorough wrench, but have you checked relays, grounds and electrical connections for corrosion/ looseness? Just trying to apply the KISS method. HTH Ps I drink Bass! B-)