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Super Charger Assistance Request

Discussion in 'Performance & Fuel' started by Goldie, Mar 2, 2011.

  1. Goldie

    Goldie Epic Member 5+ Years 1000 Posts

    I recently installed a super charger (wynjammer) with a reprogrammed PCM on my 07 Sierra. I'm running the 4.3L with a 5 speed M/T. When I disengage the clutch with a cold engine (i.e. downshifting approaching a stop) the engine revs up 700-800 rpm's. After the engine reaches operating temp it settles down and runs fine. I've checked for vacumn leaks and everyhting is fine. Can any one share some information on what might be happening and if there is anything I can do about it. The company suggested that I let my truck idle until it warms up.
  2. stephan

    stephan Rockstar 4 Years 5000 Posts

    Just a shot in the dark here Goldie, but I think this might be a good thing & is/was (re)programed in the PCM. When manual trans fluid is cold it tends to make the syncros sluggish & you need the higher RPMs so the gears will mesh on the downshifts.

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