I had a similar problem on my '02 PT 5-Speed after I installed a K&N FIPK. I took it to the dealer and it turned out that I had an intake manifold leak. The dealer replaced the intake manifold (the large black plastic piece in the front center part of the engine compartment which connects to the engine that has the ribs on top) gasket and that solved the "sounds like an air leak" problem. I think maybe somebody was leaning on the intake manifold with too much body weight. Maybe your problem is similar.
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 [IMG]|2003 PT GT 5-Speed | Mopar Stage 1 | Mopar 2.5\" Dual Exhaust | Mopar Short-Throw Shifter | Mopar HO Plastic Intake | Mopar Boost Gauge | AGP WGA/BOP | APC Carbon Fiber Taillights | Axis 19x8 Wheels/Yokohama 225/35ZR19 Parada Spec2 Tires | BTG Strut Tower Brace | BTG Billet Shorty Antenna | Eibach Anti-Sway Bars | HKS SSQV BOV | JLM Motor/Tranny Mounts | KW Variant 1 Coilovers | Maxxfab 3\" Downpipe | NGK Iridiums | Prototypepower UCP/CAI v5 | PTeazer Smoothie Roll Pan | Screamin\' Demon Coil/Livewires | StopTech Slotted Rotors/Hawk HPS Pads/Stainless Steel Lines | Unorthodox Racing Underdrive Pulley|
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