Very useful caution. Thank you. The consequences of a misguided experiment to out-smart Porsche with a diy AOS could be a damaged engine!
The old school catch cans seldom have any diaphragm or valve in them. But newer designs may have a one-way valve or even two valves. I wouldn't like to be the guinea-pig to determine the correct valve(s) or tank capacity! The options and cost of failure are daunting.
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