Greetings everyone, I conducted a smoke test to identify any boost leaks. The smoke is visible passing through the PVC valve (crankcase breather). Is this typical?
Does the valve shut when the vehicle is operational? I conducted the smoke test with the vehicle powered down.
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Might it be obstructed?
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You must detach the PCV from the intake pipe and seal the opening, or else the crankcase will become inundated with smoke.
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Is it significant if smoke infiltrates that area? It is merely a preliminary assessment utilising baby oil. The crank ventilation pipe or the PCV is experiencing a leak. I shall procure both components and subsequently conduct the test again.
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Boost leaks transpire solely post-turbo; the smoke will follow the path of least resistance, thus if there is an alternative route before reaching the turbo, it will not enter the boost system. It is essential to inspect the pipes following the turbo, intercooler, and inlet manifold to ensure that there are no potential escape routes for smoke prior to the turbo.
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Understood. I initiated the process prior to the turbo installation, addressing a leak in the intake, which I subsequently repaired. Subsequently, it began to emerge from the PVC or the associated pipe. I conducted the identical test on my brother's 430d, and there was no leakage at the PCV. This signifies a problem.
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The diaphragm in the PCV may have become rigid, which is a frequent occurrence and can be substituted; however, it is still necessary to seal it off to conduct a smoke test on the boost system. Should the PCV require substitution, it could result in uneven idling and permit oil to enter the intake.