If anyone has any thoughts they can give me great... I have been noticing a strange sound from my engine. It occurs under hard acceleration when I shift to second and third and it also happens when I'm cruising along in third and step on the gas hard. It sounds sort of like a hiss and knock sound mixed together like the engine is about to stall or something. It doesn't last long only a second or two...The car is stock except for mac axel-backs. My take is the variable cam is causing it or I have a bad fuel injector. Anyone else have this problem?