Car Problem Reports

Mercury Mountaineer Rough idle when cold due to upper intake manifold gasket leak

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Model Years Affected: 1998, 1999, 2000, 2001

Engines Affected: 4.0L V6, 4.0L V6 SOHC

The Check Engine Light will illuminate and the engine will idle roughly when cold. There are updated upper intake manifold gaskets to resolve the problem.

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