Speedy393

Turkster I had the work done in Abilene and we are trying to resolve the issue. I had a failed regen again Friday I ran I another 3 or 4 hrs and tried to regen it again. It did the same thing, ran 15 min. CEL came on with code 128 47 1 continued to regen and in about 3 min the CEL went off and completed a regen. What could be causing this?

Thanks for the info! I will check those sensors.

It has 214,000 miles on it.

Here is a picture of the first filter that was replaced.

I agree with you Challenger they are just guessing at my expense. All of the Mack dealers around me are owned by the same people so that is not an option. The first filter was changed because it was melted. They replaced it and a new 7th injector. Truck ran about 3000 miles regened 8-10 times and then failed. Filter was melted again they replaced it and the 7th injector again. This time it only ran 1500-2000 miles when it quit regening. That is when they cleaned everything and blamed it on the engine injectors and turbo. This time it lasted 1000 miles and I am getting the 128 47 1 code after it tries to regen. We are running this truck 14-16 hours a days in the oilfield and it spends 55-60% of the time idling running the pto. Right now it is parked until we can figure something out. Can't keep spending big bucks on people guessing at what is wrong with it. I am located in Midland, Tx is anybody knows someone that can fix it.

Thanks for your replies. I know this is a difficult one. They have put 3 7th injectors in the last 5 weeks and still have the same issue. When it starts blowing white and blue smoke when it is trying to do a passive regen that has to be caused by the Seventh injector doesn't it?

I will try and condense this as much as possible! We have an 2008 GU713 with the MP7 engine. It started off by not completing a regen. Took it to the local Mack Dealer and they replaced the DPF filter, Catalyst, 7th Injector and various sensors ($7500). Truck completed regen cycle at the dealership put it back to work and it regened about 3 times and then failed again. Took it back to the shop and they cleaned the DPF filter changed the sensors that were melted from the excessive heat during regen and and claimed the heat and soot buildup was being caused by bad injectors and cups. Replaced them and they said the turbo wasn't providing enough oxygen to keep the system clean so they replaced the turbo. Had the EGR cooler cleaned and more senders and sensors ($14,400). Truck ran 1500 miles and the same crap again! the truck will start blowing white smoke when driving trying to do a passive regen. We will park and hit the regen switch and it will smoke a while then clear up. About 15 mins into the regen the CEL light will come for a couple of minutes and then go out and regen will finish. But it is not completing it properly because it tries to do it again in another 30-40 miles until it derates and shuts down. The code it throws is 128 47 1 which is faulty 7th injector but they claim it is working. The picture is during a regen before they changed the injectors something is not right! I have spent $20K on this thing in the last 5 weeks and it still will not run. Any help will be greatly appreciated.

I have been following the forum for about 6 months. Lots of great info here! Thanks! I own 2 Mack trucks a 2004 CH 613 and nightmarish 2008 GU713 that will not run over 2 weeks at a time without going to the shop! I will save the details for a latter post.