Acura K23A1 2.3L Turbo: RDX Specs, Controller Identification & Maintenance
Honda / Acura · Engine Information
K23A1 · 2.3L Turbo
The original RDX gets its punch from a variable-flow turbo and a top-mounted intercooler. This port-injected K-series engine delivers 260 lb-ft through a five-speed automatic and SH-AWD.
Engine design
| Specification | Detail |
|---|---|
| Displacement | 2,300 cc |
| Bore × stroke | 86 × 99 mm |
| Compression | 8.8:1 |
| Construction / valves | Aluminum; DOHC, 16 valves; timing chain |
| Fuel / induction | Port injection; variable-flow turbo |
| Intercooler | Top-mounted air-to-air |
Codes & factory output
| Engine / version | hp | lb-ft |
|---|---|---|
| K23A1 | 240 @ 6,000 rpm | 260 @ 4,500 rpm |
U.S. & Canadian applications
| Model | Model years | Engine code | Transmission |
|---|---|---|---|
| Acura RDX · first generation | 2007–2012 | K23A1 | 5AT · SH-AWD |
Engine controllers
| Application / PCM family | Controller / hardware | Identification details |
|---|---|---|
| 37820-RWC · U.S. PCM families | Keihin · Renesas SH7058 | A51–A58 / A61–A65 / A71–A75 |
| Additional RWC revisions | Keihin · Renesas SH7058 | A81–A85 / A91–A95 |
AutoTuner identifies Keihin SH7058 for the original turbo RDX. Match the complete RWC suffix and calibration; the catalogue does not establish a universal read-file or flash-memory size.
Common issues & maintenance
- Reduced boostInspect charge pipes, control hoses and actuator operation before condemning the turbocharger. Leaks and control faults can mimic turbo wear.
- Oil & cooling neglectLow oil, overdue changes and coolant leaks threaten the turbo and chain system. Investigate smoke, oil loss or temperature changes promptly.
- Rough idle or misfireCheck ignition, fuel supply and valve clearance. Diagnosis is more useful than replacing several components at once.
Use the specified oil and premium fuel. Let the engine reach operating temperature before heavy load, and reduce load before stopping after sustained hard driving. Service the SH-AWD and automatic fluids on schedule.
References
| Topic | Source |
|---|---|
| Factory specifications | Acura 2007 RDX introduction |
| Exact PCM revisions | Hondata RDX controller table |
| ECU supplier / MCU | AutoTuner Keihin SH7058 catalogue |
