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Hi all, EA82T Auto gearbox. Does anyone know where I can get a one way valve apparently in sits in the manifold and stop oil leaking into the auto tranny by travelling down the vacuum line. I'm not sure I know exactly what I'm talking about but the auto tranny guy reckons I need a one way valve. If someone in Sydney has one please let me know, many thanks.

There is no one way valve. If you have fluid at the modulator the modulator is stuffed. At the engine end the line goes to vacumn not oil.
Steve

There is a PCV (Positive Crankcase Ventilation) valve in the manifold that is meant to be one way, if this has packed it in then you may get symptoms of excessive blow-by.

The extra oil in the intake system might be making its way into the auto vacuum line. Just an though, never worked on an ea auto, nor do I intend to.

You should be able to find a PCV valve at most wreckers, an NA one would probably be in better condition.

Oil vapour in the intake also lowers the threshold for pre-ignition. (pinging)

MY_STI wrote:There is a PCV (Positive Crankcase Ventilation) valve in the manifold that is meant to be one way, if this has packed it in then you may get symptoms of excessive blow-by.

The extra oil in the intake system might be making its way into the auto vacuum line. Just an though, never worked on an ea auto, nor do I intend to.

You should be able to find a PCV valve at most wreckers, an NA one would probably be in better condition.

Oil vapour in the intake also lowers the threshold for pre-ignition. (pinging)

He is talking about a one way valve in the line to the auto trans. They dont have one. If the modulator is holed boost pressure can vent to the auto causing the fluid to exit the dipstick hole
Steve

Steve, Can you please explain in writing ( in detail as I don't fully understand and need to show the mechanic what you have said) for me what needs to be done because the car is now doing exactly what you said it would do if a OWV was put in. The gear changes are too low and the boost is cutting in too low now. What is the PVC valve that MT STI is talking about. Tell me exactly what parts I need to or should I say are a possibly need to get to get it fixed.

Thanks very much.

Rabbitoh wrote:Steve, Can you please explain in writing ( in detail as I don't fully understand and need to show the mechanic what you have said) for me what needs to be done because the car is now doing exactly what you said it would do if a OWV was put in. The gear changes are too low and the boost is cutting in too low now. What is the PVC valve that MT STI is talking about. Tell me exactly what parts I need to or should I say are a possibly need to get to get it fixed.

Thanks very much.

MT STI is thinking of something else. Throw out the one way valve your mechanic has fitted and fit a new vacuum modulator to the trans. Follow the vacuum line down to the trans, it ends at the modulator. Screw in a new one, dont lose the pin as you remove the modulator.
Steve