MaxxForce 7 Engine Code 3055

This MaxxForce 7 diesel engine gave us a bit of a challenge with intermittent engine shutdowns. The engine code 3055 (high pressure fuel pump related) led us to a solution in the way of a TSB (technical service bulletin). Apparently the wiring harness to the high pressure oil pump was causing a lot of headaches causing an unexpected engine shutdown. This is the worst fear for any driver and for us in the shop due to the unexpected shut downs that could happen anywhere.

Getting in to this repair means work. The manifolds and heat shields have to come off to access the factory wiring harness so that took most of the time. The harness was available from our local IC dealer so all we had to do was replace it and button up the extra hardware. We removed the high pressure fuel pump which was our decision to get easier access to everything. Once assembled as you saw in the video the engine started up nicely and there were no issues while running.

The 2 fuel lines to the fuel rails were also supplied with the harness. Overall I was happy with the direction this job went in. This was a situation where the problem happened enough times the manufacturer as we know as International took a look and came up with a solution. Otherwise....I can't imagine how much time we would have spent on this job. Something like a loose wiring connection or bad pin connector would take a lot of time to detect. That's why I'm thankful that someone else did all of the troubleshooting work for us.

The engine code 3055 will lead you to the TSB in the NED (Navistar Engine Diagnostics) software. What would we do without diagnostic software. I'm telling you if you don't have access to this tool and operate diesel engines 2007 and newer there will be a lot of frustration ahead until you take your truck to the dealer. Any laptop will do and the software is worth every penny (I pay $400.00/yr here in Canada). By the way this MaxxForce 7 in the video is still running great.

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Diesel Engine
maxxforce 7
engine code 3055