This bulletin applies to 2014-2020 Cadillac vehicles.
During service of a vehicle that came in with an engine-related DTC that required a fuel injector replacement, GM reports that they have seen cases of the incorrect fuel injector being installed in the suspected cylinder. If this happens, it can lead to skewed long-term fuel trims (LTFT) and/or short-term fuel trims (STFT) during engine operation. The MIL may be on as well, accompanied by a rough idle.
Initial diagnosis may display any of the following misfire and/or fuel trim-related codes:
P0300-P0308, P050D, P0171, P1072, P0174, P0175, P2099, P219A and P219B.
Be sure to identify which injector part number you have. The eight-digit injector part number can be found on the injector body. Enter the VIN in the parts catalog and go to the fuel injector rail parts section.
If for some reason the injector has been removed and discarded or if you have all of the injectors on the bench and you’re not sure which one goes where, the best thing to do is to order the “NOM FLOW” injector part number. When fuel rails are assembled at the supplier, the injector installed in the fuel rail can be nominal, low or high-flow injector. This is done to try to get an even balance or flow across the fuel rail for emission requirements. Also, the replacement injector kits will have a different part number than the injectors, and a kit may contain one of several different injector part numbers.
