Boost leak


I have a 2002 VW Passat (5 speed manual). It started making a swishing type noise during acceleration. My regular maintenance guy tells me it’s “boost leak” but he isn’t able to locate it.

Now what do I do???



I guess find a new mechanic.


Does your Passat have a turbo or supercharger? If not, you need to see another mechanic.


You’re going to need some “blind plugs” (equipped with an air valve) for leak check. Firstly, disconnect the hoses connecting to the intake plenum AND the compressor housing outlet of the turbocharger, put the plugs inside the hoses and tighten up the clamps. Now you can “inflate” the whole system by using compressed air(through the air valve on the blind plug).

Make sure those blind plugs have a bead, otherwise, at around 0.8 bar they tend to pop-out. Good luck.


Find a new mechanic specializing in VW or at least European imports. A competent mechanic can find this too.

Its a vacuum or boost leak and are common somewhat with the 1.8T. Google “1.8T and vacuum leak” and you’ll get more results than you’ll know what to do with.