Faulty Exhaust Gas Recirculation (EGR) Temperature Sensor 1
Exhaust Gas Recirculation Temperature Sensor 1 harness is open or shorted
Exhaust Gas Recirculation Temperature Sensor 1 circuit poor electrical connection
Engine Light ON (or Service Engine Soon Warning Light)
Code P1428 Buick Description
The Exhaust Gas Recirculation (EGR) Temperature Sensors are variable resistors that measure the temperature of the exhaust gas at the inlet and outlet of the EGR cooler. The Engine Control Module (ECM) supplies 5 volts to the EGR temperature sensor signal circuit and a ground for the low reference circuit. When the EGR temperature sensor is cold, the sensor resistance is high. When the EGR temperature increases, the sensor resistance decreases. With high sensor resistance, the ECM detects a higher voltage on the EGR temperature signal circuit. With lower sensor resistance, the ECM detects a lower voltage on the EGR temperature signal circuit.
The Diagnostic Trouble Code (DTC) will be set if the ECM detects that the EGR cooler temperature sensor 1 or 2 is greater than 20°C (36°F) different from Intake Air Temperature (IAT) sensor 2.
P1428 Buick Code – EGR Temperature Sensor 1 Intake Air Temperature 2 Not Plausible