"Only certain vehicles are included in this action and nearly all new TLX V6 vehicles being delivered to dealers currently are unaffected by this stop-sale order," Chris Martin, an American Honda Motor Co. spokesman, wrote in response to an Edmunds query.
The cars are being held until "they receive specific inspection and repair instructions from Acura," he added.
Those instructions were not spelled out and the number of affected vehicles was not disclosed.
Acura will provide further information to its dealers and customers as it becomes available in the near future.
"In the interim, Acura encourages all drivers to engage the parking brake whenever parking their vehicles," Martin said.
The National Highway Traffic Safety Administration, which oversees vehicle safety in the U.S., has not posted any information about the TLX action.
A formal vehicle recall has not been issued at this point. Owners can contact American Honda Motor Co. at 1-800-382-2238.
Edmunds says: If you own a 2015 Acura TLX V6 and have any concerns, it's best to contact your dealer.