Does the automatic stay in Chap. 7 and 13 bankruptcies apply to repo's of collateral on secured loans?

I understand the secured creditor usually maintains their right to reposess collateral even if the debt is discharged. I'm wondering if the stay will help a debtor hold onto collateral during the proceedings...For example, a car they may need to get to work but that is in jeopardy of reposession.