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cylinder deactivation

I have a 2007 chevy Z71 1500 with 5.3 V8. I was wondering if there was any way to bypass cylinder deactivation to leave engine in 8 cylinder mode. I recently replaced # 7 cylinder lifters due to lifters not getting oil in 4 cylinder mode. I can see this will be an ongoing problem and can not afford 3500.00 dollar shop bills. Thanks for any help


  • edited April 2010
    That is controlled by the ECM. There should be a tuner calibration out there to give you 8 cylinders all the time. However that will kill your warranty and fuel economy.
  • edited April 2010
    Where would I find a tuner calibration? Truck has 116000 miles so already out of warranty.
  • edited April 2010
    Search under Chevy performance calibration. There are companies that sell you a module that you use to load their cal. The module also stores your original cal in case you need to go back. The company doing this for Dodge 6.7 Cummins is called bully dog.
  • edited April 2010
    Thanks just emailed bullydog to see if they could help.
  • edited April 2010
    Hi, I'm new to these forums, and more than 20 years has separated me from the automotive field, but maybe some one could explain how cylinder deactivation is tied to engine lubrication? I would have thought that engine lubrication would continue as normal regardless of how many cylinders are firing. I would have thought an issue of this type would be a lifter going bad simply due to high mileage, low oil pressure, or an oil journal that is plugged up a bit.
  • edited April 2010
    De activation leads to low temperatures and generally the moisture accumulates and lets the crud build up. If you operate under low loads for short times, this will happen to every engine. However the deactivation makes it worse.
    It would help if they rotate the firing cylinders so the temperature difference across the block would not get too much. Hey as long as it lasts through warranty is all the bean counters want.
  • edited April 2010
    Ahhh, gotcha. I hadn't considered temperature differentials with only half the cylinders firing. I should have thought about that, since I'm an IT professional. Modern day multi-core processors use a balancing act to keep all the cores working to prevent such temperature differentials, and that makes perfect sense. So I agree with you 100%. They should alternate the firing of the cylinders to keep temps more even.

    Who says you can't teach an old dog new tricks. :)
  • edited April 2010
    My question is how do you really know that was the reason it failed. Was this a mechanic's theory?

    Mechanics pull all kinds of stuff out of their #$$ to explain problems.
  • edited April 2010
    As others have said a tuner will allow you to turn off the cylinder deactivation. All the people I know with vehicles that have this feature ( mostly people with newer Dodge Rams )turned it off shortly after having their exhausts done ( straight pipes out the converters), apparently when they switch to 4 or 6 cylinder mode the engines sound ridiculously wimpy.
  • edited April 2010
    I apologize in advance for this comment but cannot resist, so here goes:
    Tim hats are complementary with straight pipes, so is a big machine gun and a lift kit.

    Did you know that they also sell a resistor for the diesel Mass Air flow sensors so you can "make smoke".
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