Fixing Valve Cover Oil Leak & Fuel Rail P0171 DTC + Cleaning A/C Evaporator In The Previa SuperVan

Previa Valve Cover Gasket is leaking oil at the bottom rear corner near the distributor shaft and dripping onto the exhaust header and all over my driveway. It appears I did a poor job with the Gasket Maker at the curved edges - that's how I gain EXPERIENCE.
More fuel rail repairs chasing an intermittent P0171 Fuel System Lean pestilence since my Head Gasket Replacement. This time I think I actually fixed it replacing the Fuel Injector Pressure Regulator...
While I have the Previa in the garage, I decided to try Toyota's 2-Step A/C Evaporator Cleaner process. This is such an easy DIY improvement for automotive A/C systems. It smells amazing and the Previa A/C finally feels like it is actually cooling the greenhouse 'hot box' Previa interior.
Car: 1994 Toyota Previa LE SC AllTrac
Thumbnail Title: Valve Cover Re-Do
Music: Oaxacon Tradition by Jimena Contreras (UA-cam Music Library)
‪@jamiecars‬

[@kurticusmaximus]

I like the tube repair.

[@u.e.u.e.]

If the P0171 would come back - there is only one safe way to find the air leak: smoke/vapour detection.
Ask an independent service near you if they have a machine that can blow "fog" (oil vapour) into the sealed air intake system. Sometimes it takes more than 30 minutes until it comes somewhere near the fuel tank or under the car or hidden near the firewall out of a micro-crack. That's where the engine is sucking un-metered air, that's causing the +15% fuel trim, that trips the engine lean code.