Hello i have a couple issues with a 1991 honda civic it vibrates a lot while in drive and even more when in reverse and has a slow rate of reaction/acceleration when you press the pedal this only happens when its in d4 ... i even floor the gas pedal and the rpms dont go over 3 to 4 thousand when its like 0-40 miles an hour

Assuming the idle speed is correctly set. Check for worn out or broken engine and tranny mounts. replace as nessesary. Check for any stored diagnostic trouble codes stored (count the blinking red light on the computer under the passenger carpet.) Check ignition timing, and also cam timing, the t-belt could be a tooth off causing the lack of acell or it could be an internal failure in the transmission. Check the throttle valve cable at the transmision for proper operation and adjustment. There's a few ideas to get you started. Lmk how it goes.