You guys on this forum are amazing as always! We finally got down in there and lo and behold, the elbow of which you speak, Rocky, had basically disintegrated but was not visible from the top side. We took a good elbow from the front of the engine (and replaced that with a short piece of silicone hose) and replaced the elbow behind engine and all is well with the world - the car runs smooth as silk, the "economy" gauge works as it should and I am absolutely loving life with my 560sl right now!!! (And what better time could that happen???) Humble motoring my SL bretheren and, as always, thank you for your words of wisdom!

Stix

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Encouragement is fertilizer for the seed of desire & the flower of accomplishment.

1986 560SL Silver/Burgundy