I have a 91 acura legend and its very hard to shift gears

SOURCE: 91 acura legend

There is a connector under floor mat on front passenger side.
With the car turned off, jump this contactor out and turn the car to on position. After 2 seconds the abs light will blink given you codes.
After you fix the problem, you will need to remove the jumper, and pull all 3 abs fuses. Wait 3 seconds a reinstall the fuses. Now plug the connector back into its holder.
Now start the car, and the code should be cleared.

SOURCE: no brake lights/lamps on 91 acura legend

Check for bad wiring at the 3rd brake light. You may find frayed or broken wiring there.

SOURCE: problems with my acura 3.2 cl not shifting

i had the same problem with my 3.2 cl type-s they had to change out some gears and replace a lot of parts in my transmission. it cost about 2500 to fix thru aamco

SOURCE: just swapped out the engine in my 1992 acura

You either have a dead battery, or a bad wiring connection.

SOURCE: How do change a Thermostat for a 91 Acura Legend

1. Drain the cooling system and remove the lower radiator hose from the thermostat housing.
2. Remove the thermostat housing bolts, the housing and the thermostat.
3. Clean the gasket mounting surfaces.
4. To install, use new gaskets and reverse the removal procedures; install the thermostat's spring end toward the engine. Torque the housing bolts to 9 ft. lbs. (12 Nm).
5. Refill and bleed the cooling system.