has anybody had thier floorboards vibrate when you take off? what is that? ive checked my motor mount, tranny mount, cv joints and tire rod ends. i cant figure out what is doing it. 04 mazda3 5dr 5 speed

 

is your exhaust loud or throaty? my firebird did this when the exhaust hit the right tone at 1700rpm

 

check ur spark plugs it might be that one of them its burn cause that happen to me it would vibrate but seance im a mechanic/tuner i know the main causes of the vibrations so i recomment u to change ur spark plugs

 

i have just changed them. i got the ngk IX. i think i found the problem. my control arm bushings are wore out. im trying to find a place to buy them without going to the dealer. thanks for your help sir.