The front brake rotors can warp and cause a vibration when braking. The rotors will need to be machined or in cases where they are worn to thin, replaced to correct this issue.
1994 Honda Civic Si Problem Reports
Most Reported 1994 Honda Civic Si Problem Reports
Plugged moon roof drains can cause a water leak inside the car, usually over the head of the driver or passengers head when turning a corner. Cleaning the drains will fix this problem.
Damaged engine mounts can lead to vibration and roughness felt in the steering wheel. A rattle in the dash and engine area may also be heard. Replacement of damaged mounts will commonly correct these issues.
Certain models can leak oil externally or allow coolant into the combustion chamber due to a faulty head gasket. The head gasket needs to be replaced to correct this problem.
Certain models can have a crowned rear brake drum that can cause a vibration when braking. The rear drums will have to be replaced to correct this issue.