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  1. R

    Proper DoD delete oil pump

    The engine I am hoping to pull apart for a delete this weekend has the worse coking in the cylinders I have ever seen in my bore scope but all of the plugs look great, GM coil packs are awesome.
  2. R

    DOD Delete Theory

    Well, literally every company that sells the parts says the cam must be changed, that's likely why there is skepticism; I just can't think of a reason why it won't work and this is a rig I bought real cheap just for the engine so I thought I would try it just to test the theory. Nothing to...
  3. R

    Proper DoD delete oil pump

    Put a bore scope in the AFM cylinders and the non AFM cylinders and you will see the difference, insufficient PCV oil mist can cause this as well (why catch cans became a thing) but a catch can will cure that issue with the PCV entirely; the DOD system will coke up either way. And that oil psi...
  4. R

    DOD Delete Theory

    There is no way to compensate in the tune, the lobes lift, duration and separation angle must be the same on all the cylinders in V8 mode; the difference is the smaller base circle before the lifter starts up the lobe. The longer DOD lifter makes up for this loss in distance so all of the...
  5. R

    Proper DoD delete oil pump

    By leaving both valves closed under cylinder deactivation the disabled cylinders have trapped air which cushions the pistons and helps the engine feel smooth when in 4 cylinder mode. The engine is designed to lubricate the cylinder from beneath and control the oil to a limited amount via the...
  6. R

    DOD Delete Theory

    They do offer a kit to do it, most DOD delete kits don't include a cam, just the option to add the cam you want; most kits also specify to verify the pushrod length needed after the heads are back on and order the appropriate lenth, don't just assume the stock pushrods will be right. People skip...
  7. R

    DOD Delete Theory

    This makes no sense, the length required is what is necessary to preload the hydraulic lifter to between 50 & 65 percent of its plunger travel to establish normal operation of the valves; which area in that straight line or which component has which individual length is irrelevant as long as the...
  8. R

    Any good resources on how to install an oil catch can?

    It goes inline between the pcv on the drivers side valve cover and the intake manifold port; no changes to the passenger side connection.
  9. R

    Proper DoD delete oil pump

    Exactly, I have never seen a compelling reason to remove the factory DOD pump; it is the best factory pump ever put in the LS series engines. In fact the TSB from GM on the pan pressure relief valve is just as ridiculous, the DOD engines use oil because of the V4 mode; it has nothing to do with...
  10. R

    DOD Delete Theory

    I ordered everything but the pushrods from Summit today, when I figure out what length to order the 8 new pushrods I will post it as well as the results of this experiment
  11. R

    DOD Delete Theory

    I won't know for certain until I do it but when a dod engine is in 8 cylinder mode I don't see how the lobe specs can differ without causing a cylinder imbalance; that is why I think the only difference is the smaller base circle to account for the extra lifter length. If that length is...
  12. R

    DOD Delete Theory

    That's what I was thinking, the lift, duration and LSA pretty much has to be the same as the non DOD lobes for the engine to run correctly; so I think they just started with a reduced base circle so all the pushrods could be the same length. Like you say it's no big deal to swap the cam later if...
  13. R

    DOD Delete Theory

    I will obviously replace the cam if there is any damage, but I seriously doubt it given the intermittent nature of the symptoms and how well it runs and sounds when the lifter seats correctly. I am not trying to save money, I usually do this with a new aftermarket cam that improves torque and...
  14. R

    DOD Delete Theory

    I have a theory that I think I am going to try, looking to bounce it off of our mechanic minded members. 2006 Envoy Denali 5.3 Low miles (98k), cylinder 1 intermittent ticking, throws misfire code when ticking. I have disabled the DOD/AFM in the PCM and now need to address the hardware, all...
  15. R

    Any tips on bug and road tar/gunk remover?

    I use diesel fuel on a rag, never had an issue with paint damage
  16. R

    2012 Tahoe 5.3 tap/misfire

    It sounds like a faiiling/sticking AFM/DOD lifter on the number one cylinder, the tap goes away when the plunger manages to snap past the dogs but it is not fully extended so it misses slightly at idle; once the RPM is increased the miss is pronounced enough for the computer to narrow down the...
  17. R

    Help - 2004 Tahoe ABS, Brake Light, Traction Control, Stabilitrak

    The ABS & Stabilitrac both use the wheel speed sensors in order to function, since you have a code for wheel speed sensor you should start with that; sometimes an error in the ABS will also trigger the brake light.
  18. R

    Truck Wont Move

    If your just verifying movement at the transmission lever when the selector is moved inside the engine doesn't have to be running, and I have set my phone on record under the vehicle then hopped in and moved the selector when I am alone.
  19. R

    I was Wrong - PCV and Fresh Air

    The port from your throttle body to the passenger valve cover does not have vacuum, it is designed to use physics and act as a pressurized line pushing air into the valve cover. If you look into the front of the throttle body you will see that this port gets access to the air stream at a...
  20. R

    re-rebuild findings - 310K mi. spark plug

    I don't see anything wrong with that A/C Delco Iridium plug, looks like it's doing fine at 310k.
  21. R

    Did I maybe fry my ECM or BCM??

    For posterity sake, when you need to use the AC compressor to fill an empty system (because you don't have access to an AC Machine) the way you do it is to remove the AC relay from the fuse box and jump the pins with a paper clip (usually pin 30 to pin 87), this bypasses the high and low...
  22. R

    No start issues again

    I never said the resistor was in the key, from my first post I said it was in the tumbler housing. No, not everything that has to do with the engine is an ECM, but every Module that Controls the Engine is an ECM. If it also controls the Transmission it is also a TCM; if it controls both it...
  23. R

    No start issues again

    The security light doesn't always flash when VATS locks out the engine, the PCM is an ECM and to reiterate; the 2004 does use a resistance range to allow the BCM to satisfy the VATS.
  24. R

    No start issues again

    That makes sense, if your ignition has "learned" your security resistor the BCM is the component that verifies that and allows the ECM to start and run the engine; if the BCM is not passing on the all clear the ECM will not let the engine start.
  25. R

    No start issues again

    His vehicle most certainly can be bypassed by using an appropriate resistor between the tumbler and the signal wire to the BCM, given the disconnected yellow wire he found inside the clamshell that is very likely what his "repairman" tried to do. The resistor in the key system was replaced by a...

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