@sarah0jean: Sounds like you don't know too much about engines. Pressure testing and smoke testing are the BEST ways to check for vacuum leaks (common trouble spots being hoses, o-rings, gaskets). When the system is pressurized, you can hear hissing and, if a smoke test, you can see the smoke escape from a supposedly sealed system, allowing you to instantly and accurately discover where air is being allowed to enter the engine post-throttle body.
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