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Old 07-18-2010, 07:07 PM   #27
Bill
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Just for grins, I'm betting that the valve that was broken was the turbocharger's dump valve (there is probably a more elaborate name for it). Imagine, if you will, that the engine is running at high RPMs, the turbo is really reved, compressing air as fast as it can - and you take your foot off the throttle. Suddenly the engine doesn't need much air, but the turbo, still rotating, is pumping air at a furious rate. To prevent a dangerous overpressure in the intake air system, the turbo assembly has a dump valve, which opens quickly to let the excess air escape back into the atmosphere, and limit the pressure. If this dump valve sticks open, the turbo can pump like mad, but the air will just be vented, and the engine will be air-starved.

Just my guess. Did your mechanic give you any details?

Bill
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