Hi,
Do you have any track on the route? If the route is down because your interface is down, I don't see any reason for the connections to remain in the conn table.
If the route is not removed because of an interface down reason, I'd look at this:
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Routing convergence & connection timers
(config)#timeout floating-conn 0:00:00
(config)#timeout conn-holddown 0:00:15
timeout floating-conn hh:mm:ss—When multiple routes exist to a network with different metrics, the ASA uses the one with the best metric at the time of connection creation. If a better route becomes available, then this timeout lets connections be closed so a connection can be reestablished to use the better route. The default is 0 (the connection never times out). To make it possible to use better routes, set the timeout to a value between 0:0:30 and 1193:0:0.
timeout conn-holddown hh:mm:ss—How long the system should maintain a connection when the route used by the connection no longer exists or is inactive. If the route does not become active within this holddown period, the connection is freed. The purpose of the connection holddown timer is to reduce the effect of route flapping, where routes might come up and go down quickly. You can reduce the holddown timer to make route convergence happen more quickly. The default is 15 seconds, the range is 00:00:00 to 00:00:15.
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Thanks,
Octavian
