what is it under the cover that says 3800 seriesII.
under this cover there is a hard plastic cover,what is this and if it is cracked and the car
revs at 4,000 rpms,what does this mean?
Typical problem for a 3800 engine, the intake manifold is cracked, they are available from most parts stores so you won't have to pay the dealers price. Replace the manifold and gaskets and the problem should go away, you may have to reset the ECM after repairs are done.
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