Air Suspension category referenceSpecial order · Estimated lead time: typically 2-4 weeks
17-18 Honda Civic Si - Airtech Pro Plus Air Suspension
Choose year, make and model to confirm this application-specific product fits — you can add it to your cart either way.
Verify fitment- Four application-specific air struts with 36-way damping and adjustable lower mounts
- Viair 444C compressor and air tank
- Digital manifold with full-colour OLED remote — four-corner independent control, no switches or gauges to wire
- All hoses, wiring and installation manuals
- Damping adjustment knob
One approved application: 2017–2018 Honda Civic Si · Adaptive Damper will not function
- Ships from Mesa, AZ
- 12-month limited warranty
- Special order: typically 2-4 weeks
Specifications — CHD421-APP
Product details
CHD421-APP is the Pro Plus air suspension for the 2017 and 2018 Honda Civic Si. A digital manifold and an OLED color remote handle four-corner, independent control, so there are no switches or gauges to wire. Four application-specific struts with 36-way damping and adjustable lower mounts sit at the corners, supported by a single Viair 444C compressor and an air tank.
The one remote shows pressure at each corner and levels the car automatically based on pressure. Hoses, wiring, manuals and the damping knob are included, and the 444C raises the car from its lowest to its highest height in as little as four seconds. The 2018 and 2019 Honda Accord are also listed, though on the Accord Touring model the adaptive damper does not function. Camber-adjustable top mounts are available for some MacPherson-strut applications, so ask a technician about this car, and confirm fitment with the year, make and model checker.
Supported features
No switches or gauges and no complex wiring. The kit is operated from a single OLED color-screen remote that displays tank and bag pressure at all four corners.
36 levels of damping adjustment on every strut using the included damping knob.
Sleeve-type and double-bellow bags engineered to match the vehicle and its OEM suspension design.
Fine-tune ride height at any pressure through the adjustable lower mount.
The single 444C can raise the car from lowest to maximum height in as little as four seconds.
Available on certain MacPherson-strut applications.
Compatible applications (3)
Choices for this system
Basic (paddle valves and gauge), Deluxe (electronic switches and remote), Pro Plus (OLED remote, four-corner control) and Executive (adds height sensors and auto-leveling) are separate part numbers for this vehicle; compare them on the Air Suspension page.
Available on certain MacPherson-strut applications; ask a technician whether they apply to this vehicle.
Installation
Bolt-on struts with supplied hoses, wiring and manuals; professional installation is recommended. Recheck the system after the first 500 miles or one month; to check for leaks, inflate to 70 psi and spray each fitting with soapy water.
Air suspension setup and careWarranty & service
12-month limited warranty to the original purchaser against defects in materials and workmanship. Racing use, exterior finish and improperly installed or modified parts are not covered; keep your original invoice for any claim.
Warranty terms and service requestsOther published pages for MPN CHD421-APP
These page names share this MPN; they do not confirm fitment. Verify your vehicle before ordering.