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New to me 2019 RST 5.3

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Hello to all, new to forum and have a few questions. Purchased a used 2019 RST with the 5.3. Not new to AFM but first truck with DFM and Auto Start/Stop.


I installed a Pulsar LT unit, programmed per instructions/videos. Maybe it's me but it seems the DFM delete function isn't working as it should but the Auto Stop/Start functions works fine.


It seems that there is still a bit of hesitation and shuddering when accelerating. 


Any thoughts or should I be considering other issues.





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Try driving in L7 at a steady speed in the 30 - 45 MPH range and then switch to either L8 or D while you have your fuel economy readout open on the dash. If it changes dramatically and you get more vibration, then DFM is active. If it stays the same, then the Pulsar is doing its job.

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