The acid level of a starter battery during service can only be adjusted by topping up with pure water.

对运行中失水的起动用蓄电池补加硫酸溶液提出质疑，强调只能补加纯水。

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Topping off the Cayenne's 22-liter AdBlue reservoir is part of the regular service schedule, but it's entirely possible to run out of the stuff between services, depending on how you drive.

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