2017-2023 L5P DURAMAX TUNING INSTRUCTIONS WITH HP TUNERS

CLICK THE LINK FOR THE INSTRUCTIONS FROM HPTUNERS: How to install the new GM E41 ECM Upgrade Kit | HP Tuners

  • CONNECT YOUR MPVI3 DEVICE TO THE OBD2 AND IF YOU HAVE A 2017-2018 INSTALL THE HP TUNERS E41 UNLOCK KIT
  • Open VCM Editor and Get a copy of the stock read.
  • Send the stock read and the SERIAL NUMBER from your MPVI3 to calcotuningmx@proton.me (We need this EVERY TIME, failure to deliver will result in a delays for file service)
  • Make sure you have at least 6 credits on the MPVI3
  • Once you receive the MOD file, flash it by following the HP Tuners instructions.
  • After the Flash is complete you need to install the FISH TUNING E41 Plug Kit for 17-19 or FISH TUNING E41 Plug Kit for 20-23
  • You now need to perform resets using either your diagnostic tool (Snap-on, etc) or you can connect to the truck with a J2534 box (Nexiq USB Link w/
  • OBD2 Connector works perfectly).
  • Setup an account with ACDelcotds.com and purchase 1 light duty subscription for the truck- the 3 day sub should be sufficient.
  • Download and install techline connect
  • Connect to the obd2 port with your J2534 connector and ensure your specific connector is selected in Techline Connect.
  • Reset ALL Emissions data listed.
  • Then unplug DEF Injector and EGR
  • If your DEF Quality sensor is bad, unfortunately you have to replace it
  • You need to unplug all of the EGR Components (See Pictures Below)

  • These trucks are unique in that any time the fuel/air ratios are thrown off (Bad MAF or MAP Sensor, or Injector Pigtails go bad, these trucks will throw a Service Emissions Message. Check for codes, do your due diligence and diagnose the problem- TUNING IS NOT THE CAUSE.
  • You will have to reset the Emissions system again upon completion of repairs.
  • WE STRONGLY ADVISE YOU HAVE YOUR CUSTOMERS KEEP SPARE INJECTOR PIGTAILS IN THEIR GLOVE BOX- THEY GO BAD ALL THE TIME!!!
  • Injector pigtails: SINGLE PIGTAIL or a SET OF PIGTAILS
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