Which engine do you have in your Caprice? Diffrent engines had diffrent ignition systems. Check/change your fuel filter first. It is located by the left rear wheel. If it is dirty it will cause hesitation. If it is plugged the fuel will not get to the engine. Another item that will cause loss of power/heitation is a bad EGR valve. This is mentioned in some other posts in the Caprice section. Check them out.
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