I really don't think that was the problem. I have a fairly new battery (about 2 years old) and I didn't have the key turned to "on" for that long in the garage. There were no signs of low battery, and the car turned over strongly for a while after the problem had happened. It seems unlikely to me that a slightly low battery (probably in the high 12.xx to low 13.xx volts range) could cause something like that.

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2003 3.0 5MT Topasblau
Purchased in 2016 and surprisingly still running