So last night when we pulled into Walla Walla, we noticed the engine was
noticeably louder. Like the noise when the valves have temporarily lost
hydraulic pressure.

There was no noticeable power loss, just noisy and disconcerting.

Does anyone have recommendations for a friendly Vanagon shop in Walla
Walla? I think it might be time to have an engine flush with ATF or Sea
Foam. But I want the help of someone who knows the engine.