The Acura RSX is a sporty hatchback that replaced the Integra. In stock form, the RSX is a very impressive car, particularly if it is an RSX-S, the high-performance derivative of the model. But, like most cars, the suspension on the RSX is a little on the high side and can also stand to be a little more stiff. Many owners upgrade their RSXs with coilovers, a high-performance setup that combines the spring and shock in an adjustable assembly.
Loosen the wheel’s lug nuts. Lift the front of the car with a floor jack. Lower it onto jack stands under either side of the car. Finish removing the front lug nuts and the wheels.
Disconnect the ABS wire with a 10-mm socket where it attaches to the strut assembly. Unbolt the bracket that holds the brake line to the strut with a 12-mm socket. Bend the cotter pin that goes through the bolt that fastens the steering arm to the suspension with the flathead screwdriver. Pull the cotter pin out with pliers.
Remove the nut with a 19-mm socket. Use the ball joint separator to separate the ball joint from the strut. Swing the steering rod out of the way. Remove the two bolts that hold the lower part of the strut assembly to the suspension with a socket.
Open the hood. Remove the three 14-mm nuts that hold the upper end of the strut to the strut tower. Support the strut assembly as you remove the last nut. Pull the strut assembly out of the car.
Install the already-assembled coilovers in the car. Insert the top end of the coilovers up into the strut tower so the studs protrude into the engine bay. Hand-tighten the upper nuts to hold the assembly in place while you install the lower end.
Install the bolts that hold the lower part of the strut assembly to the suspension. Tighten the bolts. Tighten the upper strut bolts. Slide the steering arm back onto the strut arm and tighten the nut. Install a new cotter pin through the hole in the bolt and bend the end of the cotter pin to prevent the nut from becoming unthreaded.
Bolt the ABS line and the brake fluid line back onto the strut assembly. Repeat the above steps for the opposite side of the car. Reinstall the wheels and lower the vehicle to the ground.
Open the trunk. Pull the flat panel on the bottom of the trunk out. Fold the rear seats forward. Remove the clips that hold the carpeting in place by hand. Pull the carpeting back until the nuts are exposed that hold the tops of the rear struts in place.
Loosen the lug nuts for the wheels. Raise the rear of the vehicle with a floor jack. Lower it onto a pair of jack stands under either side of the car. Finish removing the wheels. Remove the ABS wire on the strut with a socket. Remove the lower bolt that holds the strut assembly to the suspension. Remove the two upper strut nuts located in the trunk. Remove the outer camber bolts on the lower end of the strut. Remove the assembly from the car.
Insert the upper part of the new coilover so that the studs go through the holes and into the trunk. Hand-tighten the upper mounting nuts. Place a jack under the lower part of the hub where the wheel installs and jack up the suspension until the holes in the lower end of the coilover line up with the hole in the suspension. Install the lower mounting bolt. Install the camber bolt. Tighten the lower bolts and then the upper bolts.
Reinstall the ABS wire on the coilover. Repeat the above steps for the other side of the car. Reinstall the wheels. Lower the vehicle to the ground. Reinstall the carpeting that conceals the upper strut nuts. Reinstall the trunk panel. Tighten the lug nuts on all four wheels. Have the suspension aligned by a professional shop.
