whats the cost to repair the upper intake gaskets on my 98 intrigue 3.8L on 1998 Oldsmobile Intrigue

i changed the spark plugs,because the car would not start ,i notice they had lots of fuel . one's i replased them the car started.then i notice white smoke coming out threw the exhaust pipe.some one told me that i had to replase the upper intake manifold gaskets

Asked by for the 1998 Oldsmobile Intrigue
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