2021 Jeep Grand Cherokee TrackhawkFACTORY OEM SERVICE PROCEDURE

Injector Quantity Adjustment: Notes

The injector quantity adjustment, or classification of injectors describes the quantity, or fuel delivery characteristic of the injector. This will make it possible to match the Powertrain Control Module (PCM) fuel delivery strategy to the mechanical characteristics of the injector within a more narrowly graduated range. Injector classification can only be performed with a scantool.

The fuel injectors used in this vehicle have a seven digit alphanumeric code, which allows the PCM to determine the fuel quantity characteristic of each injector.

When carrying out service procedures where the injectors are removed from the cylinder head, it is important to observe the original locations of each individual injector, as installing an original injector in the wrong location, vehicle driveability and smoking concerns could result.

If an injector(s) is replaced, or if there is any concern that an injector may not be installed in its original location, the injector quantity adjustment procedure must be performed with the scan tool in order to program the quantity classification (seven digit alphanumeric code) to the corresponding cylinder in the engine control module.

Factory Service Tools

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • β€’ You smell fuel, burning insulation, or see smoke.
  • β€’ Brakes feel soft, pull hard to one side, or make grinding noises.
  • β€’ The engine overheats, stalls repeatedly, or misfires under load.
  • β€’ You are missing required tools, torque specs, or safe lifting equipment.
  • β€’ You are not confident in the next step or safety outcome.