Reference Number: 12638266. Suitable for 2014-2017 Buick Regal 2.0 L. Suitable for 2018-2020 Buick Regal Sportback 2.0 L. Suitable for 2018-2020 Buick Regal TourX 2.0 L. Diagnose engine faults: The crankshaft position sensor can also be used to diagnose engine faults.