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    Guest Message by DevFuse
     

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    Egr Block



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    8 replies to this topic

    #1 OFFLINE   JerryB

    JerryB

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    Posted 17 June 2010 - 10:11 PM

    Did anyone try putting the plate in to block the EGR yet? 40,000 miles on running mine blocked and fuel mileage is up and throwing no codes so the test goes on.

    #2 OFFLINE   rhasler

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    Posted 17 June 2010 - 10:54 PM

    Did anyone try putting the plate in to block the EGR yet? 40,000 miles on running mine blocked and fuel mileage is up and throwing no codes so the test goes on.

    I've read your other posts about this and can't figure out why it would work unless your mass air flow tube had bad sensors in it that were feeding the mass flow ecm bad information. Maybe you got lucky and got some parts that were "bad" in just the right way!
    "Mebbe I'm too ugly and stupid to give up!"

    #3 OFFLINE   fjh

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    Posted 18 June 2010 - 07:14 AM

    I've read your other posts about this and can't figure out why it would work unless your mass air flow tube had bad sensors in it that were feeding the mass flow ecm bad information. Maybe you got lucky and got some parts that were "bad" in just the right way!

    I got two customers running with the plate. the one claims to be getting 40 bucks a day better fuel milage with egr code The other more power, but no milage gain as of yet with an egr code!Why you have no egr code is a real mistery as 68 mentioned before its real odd!Having said that the egr code took along time to come on with the one truck several hundred miles but it did show up.

    #4 OFFLINE   JerryB

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    Posted 18 June 2010 - 08:03 AM

    I got two customers running with the plate. the one claims to be getting 40 bucks a day better fuel milage with egr code The other more power, but no milage gain as of yet with an egr code!Why you have no egr code is a real mistery as 68 mentioned before its real odd!Having said that the egr code took along time to come on with the one truck several hundred miles but it did show up.


    According to what I've read I think I was supposed to have a 4-9 code but so far there's no code so maybe as you guys say the sensor is bad. My fuel mileage went up on average about 1.25 mpg and I have slightly more power.

    #5 OFFLINE   rhasler

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    Posted 18 June 2010 - 08:20 AM

    According to what I've read I think I was supposed to have a 4-9 code but so far there's no code so maybe as you guys say the sensor is bad. My fuel mileage went up on average about 1.25 mpg and I have slightly more power.

    I guess that means if it is broke don't fix it. That's a pretty big increase.
    "Mebbe I'm too ugly and stupid to give up!"

    #6 OFFLINE   JerryB

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    Posted 18 June 2010 - 09:00 AM

    I guess that means if it is broke don't fix it. That's a pretty big increase.


    I can't give all the credit to the plate for better fuel mileage because at the same time I blocked it I put on a new turbo. Maybe the turbo and block combined to help?? I've been having exceptionally good luck with the old gal since fjh and MackPro talked me through the coolant pushing and turbo blowing nightmare. I had the truck at local Mack 5 different times with no improvements but then you guys here at Big Mack talked me through and we fixed it.

    #7 OFFLINE   rhasler

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    Posted 18 June 2010 - 11:54 PM

    According to what I've read I think I was supposed to have a 4-9 code but so far there's no code so maybe as you guys say the sensor is bad. My fuel mileage went up on average about 1.25 mpg and I have slightly more power.

    4-9 is for the EGR valve. 5-8 and 5-9 are for the mass flow sensors. The VMAC III manual doesn't say these will derate the enging when set and I can't remember if they do. I suspect that when the faults set normally the engine ecu has no idea how much EGR is going into the engine so it starts actuating the valve, this causes all kinds of weird engine behavior due to increases in EGR gas introduced into the cylinders. With the plate installed I think it (the engine ecu) is doing the same thing, but since the valve is blocked off the gas can't get back to the cylinders. This also helps explain a modest power boost, since the valve is closed off there is more exhaust gas pressure in the manifold causing the turbo to spin faster. Of course this is all hypothetical and it still doesn't explain why you have no codes set.
    "Mebbe I'm too ugly and stupid to give up!"

    #8 OFFLINE   bigen

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    Posted 19 June 2010 - 12:33 AM

    to block or not to block, this question has cost me a lot of sleep.
    trucks running good, getting 5.75 mpg
    but i am thinking about taking out the coolant screen???????????????

    #9 OFFLINE   fjh

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    Posted 19 June 2010 - 06:35 PM

    to block or not to block, this question has cost me a lot of sleep.
    trucks running good, getting 5.75 mpg
    but i am thinking about taking out the coolant screen???????????????

    I would block the egr before taking out the screen!




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