The P1129 code in your 2021 Acura NSX indicates the fuel system is running too rich on bank 2. This Honda/Acura-specific code signals the ECU is removing maximum fuel but still can't achieve the correct air/fuel ratio on the rear bank.
NSX Fuel System Complexity
The NSX's twin-turbo V6 uses sophisticated fuel injection with individual cylinder control. Bank 2 (rear bank) running rich indicates excess fuel or insufficient air on those cylinders.
Common Causes of P1129
- Leaking fuel injectors on bank 2
- Faulty MAF sensor
- Excessive fuel pressure
- O2 sensor failure
- EVAP purge issues
- ECU calibration problems
Symptoms of Rich Condition
- Check engine light on
- Black smoke from exhaust
- Strong fuel smell
- Spark plug fouling
- Poor fuel economy
- Possible catalytic converter damage
NSX Performance Implications
The NSX is a precision supercar where fuel mixture is critical for performance. Rich conditions affect power output and can damage expensive components.