What causes GM code 23?

Open MAT or intake air temp sensor circuit Unplugged sensor connector Failed sensor reading far colder than actual air Corroded harness connector raising resistance

How do I fix GM code 23?

Compare scan tool air temp to actual ambient temperature Inspect the sensor connector and air cleaner duct wiring Measure sensor resistance against the factory temperature chart Repair the open circuit before replacing the sensor On carbureted models check the manifold air temp sensor in the intake

23 Intake Air Temp Sensor Error Low Temp Indicated

Q: What does GM code 23 mean?

GM code 23. Intake Air Temp Sensor Error Low Temp Indicated. Applies to 1986-1995 GM cars and C/K trucks, Camaro, Corvette.

Make: GM (1982-1995)
Category: Powertrain - Fuel/Air Metering
Severity: Check Engine Light
Applies to: 1986-1995 GM cars and C/K trucks, Camaro, Corvette

How to read it

Code 23 reads as 2 flashes, pause, 3 flashes on the check-engine light. Jump terminals A and B on the ALDL connector with the key off, then turn the key on with the engine off and count the check-engine flashes.

What does GM code 23 mean?

23. Intake Air Temp Sensor Error Low Temp Indicated. This code sets when your vehicle computer detects intake air temp sensor error low temp indicated.

Common causes of 23

Open MAT or intake air temp sensor circuit
Unplugged sensor connector
Failed sensor reading far colder than actual air
Corroded harness connector raising resistance

How to fix 23

Compare scan tool air temp to actual ambient temperature
Inspect the sensor connector and air cleaner duct wiring
Measure sensor resistance against the factory temperature chart
Repair the open circuit before replacing the sensor
On carbureted models check the manifold air temp sensor in the intake