The Kill Reflex

The original title was going to be Soda Cracker.

In the shootout between Fred Williamson and Bo Svenson, Svenson is driving his car to get away and the rear window glass is missing. When Svenson gets out to shoot at Williamson, the glass is intact and is then shot out by Williamson. Svenson gets back into the car to get away, the rear window glass is intact. Svenson backs his car toward Williamson, the glass is again missing.