It is super complicated and very fact specific. Only an attorney that is familiar with the specific facts of your case could even begin to give you an answer.
If the police are impounding the vehicle (as they often do subsequent to an arrest), they are required to do an inventory search of the entire vehicle. They do not need a warrant in this situation.
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Most agencies have set policies regarding inventoring the contents of a car they are impounding. Any evidence of criminal activity they find during the inventory may be used against you. It gets very fact-specific after that.