I am in the process of replacing motor mounts in my 1994 Accord EX; 2.2L F22B1 w/Automatic Trans. There is a valve assembly on the firewall that has one hose going to the rear motor mount and another that isn’t connected to anything. (It's the circled hose in the picture.) What is the second hose supposed to be connected to, if anything?

 

Vacuum port in the intake manifold.

 

That was it. Hose came off. Reconnected and no more rough idle. Still some vibration when accelerating in the 55-65 mph range; should probably still replace rear mount.

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