[Beard]

thanks for very much. Once the engine is offed, the vacuum gauge start dropping and before 10 seconds, it is all down to zero. There's no oil in the vacuum reservoir and i still can figure out if there's any leakage. My gears also take longer time to change
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Hello.
10 Seconds???
This indicates that you have a vacuum leak.
Most likely the vacuum pump is worn out. And how did you know that there was no engine oil in the receiver? To see this, you need to remove the valve cover and try to drain the oil from the receiver by placing the valve cover vertically so that the receiver fittings look down. Replace the pressure converter, it is responsible for the boost pressure!!!
When the engine is idling, the boost pressure should be approximately equal to atmospheric pressure.
approx. 10xx m.bar

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