Ruff idle.no misfires. I hear a hiss under the intake. Bank 1 is running lean at -30% any ideas.

 

Welcome to the forum

-30% is RICH
+30% is Lean

Hiss reads like a vacuum leak and bank 1 is passenger side of a V6/V8 Ford engine
Vacuum leak would cause + fuel trims, lean code

Lean and rich are not related to fuel, these mean computers calculations were off either lean or rich, not that engine is actually running lean or rich