Pressure test 101- how to find boost leaks

//Pressure test 101- how to find boost leaks

The 996 TT ® are notorious for having boost and vacuum leaks. In most cases it is the dreaded #16 check valve that’s connected on top of the engine to a black plastic hose that drops down on the driver side pre turbo piping. However, even many after marker DV’s leak themselves form the fittings, or even worse- the shop that swaps the dvs for a client never checks for leaks after the install. The Dv’s are connected to a web of vacuum hoses with a often failing F hose that bursts as well. The other major location is behind the oil filter where there are 3 vacuum lines connected to the intake plenum. Often they pop off or are loose to to heat.  Then as we proceed from left to right, the throttle body O ring sometimes gives as well. further to the right side of the motor, the fuel pressure regulator often pops off and may create a dangerous condition as the car will lean out dramatically on boost since the fuel rail does not get  any pressure anymore. Simple zip ties can take care most of the issues.  Other human errors that cause major boost leak issues are after market boost hoses with after market intercoolers. The market is swamped with low quality parts made for pennies on the dollar. Often clients make classic mistakes trying to save a few dollars and end up buying themselves a lot of problems. The boost hoses do not fit properly into intercoolers, pop off the intercoolers, or the intercoolers themselves leak. I cannot stress this enough, if you buy , buy quality parts that you know and trust the manufacturer. We at Markski tuning make all intercoolers from scratch per order be it 3.5″, 4.5″ or even monster 6″. Half of the leak issues is caused by human error. The other half is wear and tear of vacuum lines. Our simple pressure tester will find all the issues…


2017-08-06T19:48:57+00:00 November 5th, 2015|0 Comments

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