The fuel injector flow rate identifier for 2020 Chevrolet Silverado 1500 and GMC Sierra 1500 pickups equipped with the I-6 diesel engine (RPO LM2) is stored in the Engine Control Module (ECM). The identifier also appears on the injector itself, indicating its actual flow rate. (This is used to compensate for manufacturing tolerances of the injectors.)
You also will find that the engine has an injector flow rate identifier label located on the side of the charge air
cooler. Note that this label is only valid if all six of the original injectors are still installed in the engine. Should a
fuel injector or engine replacement be required, the label must be removed and discarded. The service engine
will come with new fuel injectors and a new flow rate identifier label.
When replacing a fuel injector, take a photo of the flow rates on the injector prior to installation. When replacing the ECM, it’s also a good idea to take a photo of the flow rates in GDS2 prior to removing the old unit.
With the service engine, the label will be located on the side of the camshaft cover. It is only valid, however, if all six of the original injectors are still installed in the engine. If a fuel injector requires replacement, the label must be removed and discarded.
If the labels have been removed from the OEM and/or service engine, refer to the identifier information that appears on each injector.