Alternative power-plants and transplants (GTi, Porsche, Subaru, Audi, diesel etc). Discussion and Q&A last answered over 2 years ago.
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The brakes will always loose their servo effect without the vacuum from an idling engine. Just push HARDER, like we use to before brake servos and power steering (which wasn't that long ago)
Probbaly nothing to do with a vacuum one-way valve in this instance. But some vehicles will have a vacuum accumulator to keep them servoing a bit longer after an engine cutout.
well its stopped stalling now and it idle's much higher, apperently the brakes wont loose pressure now either when it stalls...and its stoped going swoooooosh when you turn the engine off, no air escaping i suppose.