Maxforce 13 Low Power, will not pull at higher speeds.

I had a similar issue, dealer said I had some aeration in the fuel lines? It started all of a sudden when I left a rest area, low power and any slight incline just slaughtered it. I don't know how you managed to keep it going a year like that holy moly. I had to run at night to avoid traffic, had on flashers on basically the whole time. Somehow got it home though, and they fixed it.

Now I had a new issue the other day. Gas stopped responding, I turned it off and on while still rolling. It responded but very rough and low power. Parked it, turned it off and disconnected battery for 15 mins. Turned it back on, and it would die after a few seconds. No mechanics nearby, so got it towed to a dealer. At the dealer it fired up like nothing ever happened. Dealer spent 4 hours diagnosing and couldn't figure it out. Opened valve cover and checked injector wires too. Drove it 6 hours yesterday. Hard to be upset ifbits working now, but wondering if it will happen again. Found a thread here with lots of people having similar issues. Seems most likely culprit is a loose connection somewhere, possibly under the panel by the clutch.

Please folks, help others and post when you figure out what the problem is.

 

Knock on wood, injectors are one of the parts on a Maxxforce that we hardly ever have to change. I think your first step is to see a tech that knows those engines and has Navistar Engine Diagnostics software. I'm not a fan of generic 3rd party software for exactly the same reason as the problems you are having. I have several posts here about Maxxforce and low power diag. Check some of these out;
2012 maxxforce 13 boost surging
2012 maxxforce 13 boost surging
2013 Prostar Plus Question - Need your opinion
2013 Prostar Plus Question - Need your opinion

 

Boost control is one thing that would reset with a key cycle, and also the fuel pressure control valve on the fuel pump. Going on a 0-60 lugdown performance snapshot during the low power moments would point out what is below spec and then a proper diag path can start from there.

 

I wish mine would have stored some kind if fault codes from my power failure. At one point my dash lit up like a Christmas tree and it gave me "electrical fault" message. Then went away. But when the dealer read the codes, it wasn't there.

 

If you are worried about the price of the nexiq I would tell you if it can save you even a few trips to dealer to check and reset codes it will pay for itself. Also you can always sell it for a small loss on ebay when you are done with it. I would be hesitant on the Chinese clones but if you do go that route please report back on it I have heard nothing but bad about them. Also NED can be found for free and you can use it with relatively easy workarounds. The same cannot be said for newer navistar software like DLB because it needs an online connection to a navistar account for most tasks.