i have a 91 civic ex and whenever i lay on the brakes kinda hard i feel and hear a knocking sound from right underneath my foot or around that area, this happens sometimes when im starting from a stop. it does not really happen when i gently lay on the brakes. i have a b16 in there and i believe i have some pretty old engine mounts, they were installed by the previous owner and according to him were one of the first mounts made for it. what could be causing that sound? could it possibly be the engine just moving suddenly a bit and a small part of it knocking into the firewall? thanks.

 

help please

 

might be your axel

 

if it was the axle wouldnt it make that knocking sound when i am turning instead of when i am braking kinda hard or going from a stop? are there any procedures or test i can run to figure it out? thanks.