So you can get the car into gear but when you start to let up on the clutch (engage it) the car starts to shake? And you mentioned it also happens when you're shifting into second. Does the sound only happen after you have it into gear and when you're re-engaging the clutch? Or are you starting off in 2nd gear? If your car is already in the gear, then it can't be a synchro problem. If it's happening when you're letting up on the clutch, then the problem is most likely coming from that area. Hope this helps.
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'00 Prelude
Black 5spd
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'00 Prelude
Black 5spd