The economy gauge is connected to the same vacuum cable as the vacuum pods are. So yes it could be connected, or in this case...disconnected.

The vacuum line runs from the bottom right hand corner nearest driver fender of the intake manifold. The line runs up through the engine firewall above the ABS into a Y vacuum connection. One for the vacuum pod unit behind the glovebox, the other to the cluster.

My bet is either the Y connect has come undone, or the one at the intake manifold.

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