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Mackpro last won the day on February 10 2012

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  1. Mackpro

    Need computer best reasonable price

    You need the VECU . Those also failed like crazy due to the leaking windshields of the R series and the way they are mounted from the factory
  2. Mackpro

    Need computer best reasonable price

    Is it in a RD? If so, early RD’s with ETECHs were know to fry engine ECM’s a lot . The engine ECM’s were bolted to the RH side of the block , when the front and rear motor mounts would wear out the engine could lean enough when going off road or in a hard pull and the frame mounted fuel filter stand would hit the engines ecm and barely dent it and it would fry. Seen it a bunch. If this is the case , check or replace the front and rear motor mount rubbers and bolts
  3. Mackpro

    Fuel pressure

    From what I remember the Original style ETECH engines came with 60 psi overflow valve, there latter came a 100 psi valve that solved some rough idle issues in a few UPS trucks we saw. The ETECH overflow valve has a barb on it for the plastic fuel return lines from the head/injectors. This is a easy way to tell a ETECH engine from a CCRS/ASET engines. Plastic line= ETECH. No plastic line =CCRS/ASET. Starting in 2002 with the CCRS on through the to end of the ASET engines the the fuel valve opened at 60 psi. So fuel psi should be at 60 + at idle and go up as rpms increase. If psi goes down as rpms go up you got a problem.
  4. Mackpro

    Need computer best reasonable price

    12MS517BM is usually current part number for a 99-01 ETECH engine ecm. We used to reflash used ones and put the correct data in then to match the truck/engine. As long as it was a ecm part number that interchanged with the original it would work. Mack still has plenty of Reman ECM’s for the ETECH (VMAC 3) style engines . However VMAC 1&2 are not looking good. A Reman ecm also comes only with a basic data in it for the engine to run, usually about 250 HP. You gotta get it flashed to match your original engine.
  5. Mackpro

    2008 mack mp8 nox sensor location

    It does nothing but turn the light on in your case. However. On a 2010 and up with DEF system, it’s a big deal if there is a issue.
  6. Mackpro

    Mack CXU 613 2011 DPF Problems

    We have a local guy doing deletes here with good results. At least 15 Macks that I can count. The trucks all stay local or within 150 miles of here. There are no DOT emissions testing requirements around here so it’s kinda “Don’t Ask /Don’t Tell”. Only problem we had was when changing over the Borg Warner Cool logic fan clutch to the new style fan clutch, you have to reflash the engine ECM for it to work correctly. This wipes out the delete program so the customer has to go back and get it re-tuned. The corporate fleet I work for now is all Mack so no deletes but they buy the maximum extended warranty and it sure pays for itself.
  7. Mackpro

    MP7 engine

    FMI 3 or 5 could be the harness end as Steeler said . FMI 7 with miss or running rough could be oil control valve stuck open or stuck engine brake plunger on rocker arm
  8. Mackpro

    MP7 engine

    +1 on what Steeler said. Also , there is another bulletin on injectior fault code due to the engine brake malfunctioning. I believe it’s only on the MP7 that this would happen on. The FMI is key in determining what to do next
  9. Mackpro

    Allison code P0843

    There was a Allison Guru on either a school bus fourm or a motor home forum that had lots of good tech info on the Allison’s .
  10. Mackpro

    Fan clutch

    We have zero issues with the Horton 2 speed air fan clutches on the AI CV’s like yours. Wonder what brand they are selling you?
  11. Mackpro

    In-Frame on a MP-8

    Valve spring failure and bull gear failures can be a death sentence to these truck when getting over the 750,000 mile mark. We had 3 parked out back of my old work that were just to costly to repair. You do a in-frame on a million mile engine for $15,000 then only to have the bull gear go out or valve spring break later down the road. These engines are very labor intensive and the only way I would proceed would be a complete reman Mack engine. Every thing new/rebuilt and under warranty. Then you gotta ask, is this $25,000-30,000 truck worth a $30,000 engine? Roll the dice and truck on till a major failure then part it out or off to the scrap metal business, that's the way it seems to work around here sadly.
  12. Mackpro

    97 Mac e7 ch613

    Had the same thing happen to me on an old CH . I had to turn the crankshaft just right for it to clear.
  13. Mackpro

    Derate warning

    Message set to ya about fault code/service bulletin
  14. Mackpro

    Derate warning

    If the previous work was done in your shop and you know which laptop was used, you can go to “latest selections” and chose the truck from the list and connect ( you actually don’t have to be hooked to the truck to do this). Then go to “product history “ at the top. You can go back and view the fault codes from the other times that laptop was hooked to that truck.
  15. Mackpro

    Derate warning

    Also , what was the actual fault code number. I saved all my tech bulletins and might have one dealing with the code

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