Yeah, it was me that suggested the intake manifold.

My (former) independent mechanic said he sprayed water at the intake manifold seal to check for a leak and said he couldn't find one. He gave up on the vibration and told me to take it to the dealer.

I took it to the dealer, they declared that the intake manifold seal was leaking. I think it cost around $400 to replace the gasket, and my problem was 100% solved.

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Paul S.

2001 E430, Bourdeaux Red, Oyster interior.
79,200 miles.

1973 280SE 4.5, 170,000 miles. 568 Signal Red, Black MB Tex. "The Red Baron".