[HEUI Lewis]

I did look into the edge tuner for my 2001 24 valve Cummins many years ago. The fact that they wanted you to tap into the wiring harness is butchering the electrical system. Had they engineered a connector harness with gold plated contacts connectors I might have considered it. I don’t know what your configuration is. But be skeptical. My neighbor kid bought the 6.0 years ago a story from hell after the second one. Some wires got pinched up on the alternator side raised hell with the FICM. Lucky he didn’t burn it down. I am no fan of 6.0, but your problem is sounding similar. If that Edge tuner isn’t plug and play I would throw it in the trash. I was a electrical contact connector inspector for military parts a few years ago and have no respect for anything that isn’t Gold plated .

This is some good info, but I can’t help much on the Edge module (I didn’t put it in), but I could look at it and see if it is plug and play. As far as the pinched wires, I could have a similar problem. I can go over my work again, and make sure no wires got damaged by me. It was fine when it went in the shop for repair, and it came out with poor throttle response. Something very well could’ve happened during the repair job.

 

[VWrabbitdiesel1982]

Neighbor kid was frying the ficm with the pinched wires as his father described. Sound like your on the right path.

 

[HEUI Lewis]

Alright, so I've been working on trying to find the problem for the past few days, and I have come up completely empty handed. I checked over pretty much everything Bismic suggested and found no evident damage to the wiring. When the engine revs in place, it climbs to over 4000 rpm and sounds like a healthy, normal 6.0 (I think...), but it is a completely different story on the road. Absolutely no boost, I am guessing because it isn't building enough exhaust pressure. It sounds like its pulling something, but obviously, it isn't.

I have considered that maybe the pedal is the culprit, but I am hesitant to replace it. I don't see how the pedal could be the problem when it hasn't driven for a while. Pedals don't just go bad when they're unused for a little while, do they?

@bismic Do you have any pictures by chance of those locations you mentioned in your first reply. I can inspect them again, but it would be nice to know the exact locations so that I don't miss anything. If you don't, no problem! Also, I've tried to follow the wires from the pedal to the engine compartment by following the colors, but I can never find those same colors coming out from the firewall... Any tips?

 

[HEUI Lewis]

Figured I'd update this thread because I have a possible theory for at least part of the problem. Note: before it died in September, the truck kinda "resolved" its own problem, and the throttle response was much better. It kept throwing the same codes though.

As mentioned, this problem showed up after I tore everything apart to replace the oil cooler gasket. During intake manifold removal, I discovered the nut that holds the FICM ground connection was torqued down with the intake bolt. Therefore, my wrench broke the whole bolt free, instead of just the nut. I tried everything I could to separate them, but couldn't, so I cut it (planned on fixing it).

During reassembly, I overlooked this.

Upon tearing into the truck again after HPOP self-destruction, I saw the broken connection, and have now fixed the harness! When the truck is running, we'll have to see if anything gets better.

It makes sense that FICM codes and low power could be a result of this mistake. However, would other electrical codes such as Throttle Position Sensor and Generator Lamp Circuit appear because of this? FYI, the alternator seemed healthy while it was running (12-13V at idle). Will probably get batteries load tested while everything is apart. I am also carefully inspecting the various wiring for chafing.

I am not certain that this is the problem, but it needed to be fixed regardless.

Thank you all for your help on this thread and others!

 

[bismic]

12-13 volts at idle isn't acceptable. You need at least in the mid 13's.

 

[HEUI Lewis]

Good to know, it may be time for an alternator anyway (it is squeaking) .

It would usually start out at around 13.35 and drop to 12-13 after about 45 seconds of idling. it must be around 13.5 at all times?

 

[bismic]

It should after the glow plugs turn off.