P244B Buick Diesel Particulate Filter Differential Pressure Too High Bank 1

P244C Buick Exhaust Temperature Too Low For Particulate Filter Regeneration Bank 1

Possible causes
– Check coolant level
– Check fuel quality
– Faulty Upstream Exhaust Temperature
– Upstream Exhaust Temperature harness is open or shorted
– Upstream Exhaust Temperature circuit poor electrical connection
– Inspect tailpipes for abnormal sediment; for example black soot, white ash, oil, coolant, or fuel
– Inspect vehicle for coolant, oil and fuel leaks
Symptoms
– Engine Light ON (or Service Engine Soon Warning Light)
P244C Buick Description

The sensor is located at the catalytic converter. The temperature sensor informs the ECM as to the temperature of the exhaust gases after they have passed through the turbo, upstream of the catalytic converter.

The sensor is a NTC type resistor, which measures the temperature of the exhaust gases. The resistance, and so the voltage drop at the sensor will alter depending on exhaust gas temperature.

Buick Vehicle:Buick Regal – ?Buick Riviera – ?Buick LaCrosse – ?David Dunbar Buick – Buick Century – Buick LaCrosse – Buick LeSabre – Buick Lucerne – Buick Park Avenue – Buick Regal – Buick Verano – Buick Enclave – Buick Encore – Buick Rainier – Buick Rendezvous – Buick Terraza – Buick Riviera