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Porch Pup
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About Rockwell

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    Old Iron Expert

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    New Jersey

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  1. Rockwell

    Turbo Actuator

    There is a tool that OTR Performance sells that will reset learned data, reset ECM/ACM faults and reset soot level. Cost is about $400.00, but sure beats a tow when you derate from emissions or some such. Also a great tool to help you weed out false positives. Often times, if your able to clear the code, it never comes back. Simply plug it into the OBD port, hold fuel pedal 30 seconds and done. They say this "performs resets at the dealer level". Might help you for Actuator installation if all you need is to reset learned data without having to do any programming. Just an FYI.
  2. Hey all, So I have heard many times that the reason for the known bullgear failure (retaining nut backing off) was due to Mack raising the oil operating temp to 230 degrees. I do not see any evidence that my truck has had the Pinning Technique done, but I`m also not 100% sure. Mack tells me there are no outstanding recalls for my truck. I am having no issues with my truck whatsoever, this is more out of curiosity. My truck, a 2011 MP8 , cruises at 210-214 degrees oil temp and Im curious as to why? Shouldn't this year engine`s oil be running at or near 230 degrees? And thereby have been affected by the bullgear nut backing off.? Why does my oil stay so cool if they raised the temp to 230? My motor currently has 600K on the clock. (on its 3rd set of cups/injectors lol) Any insight is greatly appreciated.
  3. Rockwell

    Mack lossing power

    Do you know what your exhaust temp is when this happens? Boost? Have you altered the exhaust in any way? I've experienced more or less what you describe due to a clogged exhaust. Created so much Back pressure that eventually the stainless flex turbo pipe expanded itself to about 4 times its size. I had no throttle, no power, zero boost. Truck would die, basically smother itself. Would start back up, and repeat. Check for boost leaks, but also check the exhaust side. Plugged DOC, DPF, or SCR media will create what you describe. Although it should be throwing codes and calling for a regen. But I don't know year of your truck.
  4. Rockwell

    Hard start drives great ?

    From all my research, it seems this is a classic symptom of injectors/cups failing. The failure creates a situation where you lose prime. I will also tell you I've been nursing this problem for months. Other than difficulty starting, the truck runs strong. Sometimes I will even have to use the primer pump for 4 or 5 pumps to get life. Point is, at least for me, it is not $6K immediately! Seems you can nurse it along long enough to get your bucks in a row. I'm sure once cooler weather sets in, it may become a more immediate repair.
  5. Rockwell

    2004 Vision is a pain.

    So hey, hows the truck doing?
  6. Just wanted to follow up on this post with what the remedy turned out to be for me. Before this happened I had to replace battery cables. When hooking up the positive cables, I hooked the Positive starter cable and the ACM positive cable to the same battery stud. (prior to this they were each on a different positive battery stud). As a long shot, I decided to put the cables back exactly the way they were and POOF, problem gone. How this has any effect whatsoever i have no clue since all the batteries are connected inline to one another. All I know is my problem is gone. Maybe this will help another down the line. Thank you again fjh for all your feedback!
  7. Many thanks for your responses and suggestions fjh. When you say ambient air temp sensor, is this the same sensor that tells the dash display the outside air temp? I know that sensor is malfunctioning because sometimes i will get lightning bolt and my outside temp will disappear and just two lines appear - -. Lightning bolt goes out and temp reappears. Is this the same sensor the ECU relies on? If so, is the location in the drivers side mirror housing as I've heard? I still don't understand the correlation between this erratic idle and the parking brake, but there is obviously a connection.
  8. Thanks for that feedback. Climate is about 75F. Truck has never done this before, now it does it every time I apply the parking brake and ONLY when I apply the parking brake. As I said, truck runs absolutely perfect and has no active codes.
  9. This is a really weird one... 2011 Mack CXU613, 445 MP8, 580K miles. Whenever I set the Parking brake (yellow knob), my idle shoots way up. Set Brake, motor will idle at 650 RPM for about 5 seconds, then you hear the turbo begin to spool up and the motor revs up to 1200 rpm, as soon as it gets to about 1200rpm, you hear a slight and rapid thumping noise (almost as if the air compressor is kickin on?). At this point the motor will then fall back to 700 and idle normal. It will not do it again unless you release the parking brake and reapply. This ONLY happens when you set the yellow parking brake. Does not happen if I use trailer valve (red knob) to park. Does not happen if i drop to idle at a stop. Only when the yellow parking brake is engaged. This condition just suddenly started out of nowhere, nothing leading up to it. Other than that, everything else about the truck is aces. Starts, runs, pulls great! All temp/pressure gauges are normal. Any ideas anyone? Thank you
  10. Much appreciated Mackpro!
  11. Can anyone tell me the location for exhaust temp sending unit? 2011 CXU 613, MP8. I need the sending unit for the Pyro Guage on dash. Mine is going from 240 to 1250 degrees in sporadic flashes. Is it located in the dpf body? Thank you
  12. Rockwell

    Anthem production

    Absolutely, at least here in the Northeast, NJ, NY, PA. Freightliner reins dominate with Volvo a close 2nd. Good observation though 👍
  13. Rockwell

    Anthem production

    I can't get over the way the roof line cuts in so severely over the cab doors. Looks to me like it would be Niagara Falls upon entry and exit in the rain, nevermind ice and snow falling from there. Just looks almost as clumsy as the hood mirrors.
  14. Rockwell

    2018 mp7 turbo problems

    So horribly sad what has become of tough American Bulldog. I feel your pain and wish you swift resolution. Down time kills.
  15. Rockwell

    egr cooler blocked

    I had this exact same problem, but my MP8 is 2011 with 570K on the clock. They removed the EGR cooler and sent it out to be cleaned.

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