Answer
Nov 30, 2024 - 06:51 PM
Code 23 on a 1985 Corvette indicates a Manifold Air Temperature (MAT) Circuit High Voltage issue. This occurs when the Engine Control Module (ECM) detects a higher-than-normal voltage signal from the MAT sensor.
What It Means and Its Impact:
- The MAT sensor measures the temperature of the air entering the intake manifold, providing critical data to the ECM for adjusting fuel and ignition timing.
- A high voltage reading typically suggests a fault with the MAT sensor, its wiring, or the ECM's ability to process the signal.
- This issue may prevent the ECM from entering closed-loop mode, where the system optimizes fuel mixture based on real-time data, potentially affecting engine performance and fuel efficiency.
Possible Causes of Code 23:
- Faulty MAT sensor
- Damaged or corroded wiring or connectors
- Poor ground connections
- ECM malfunction (less common)
Steps to Address Code 23:
- Inspect the MAT sensor and its wiring for visible damage or corrosion.
- Test the sensor using a multimeter to ensure it is providing correct resistance readings based on the air temperature.
- Repair or replace faulty components as necessary.
- Clear the code and test drive the vehicle to verify the issue is resolved.
For detailed diagnostics and repair steps, referring to a repair manual for the 1985 Corvette can provide comprehensive guidance and specifications. Regular sensor checks can help maintain optimal engine performance.
