Hi Folks,


This is my first post here, so bear with me please!


I have a 2004 2500HD with the LLY Duramax. I have about 4200 miles on the clock so far. By way of background, I installed an auxiliary fuel tank/toolbox combo way back in April, soon after getting the truck. Whether or not this is remotely important may become clear later. I have used this aux tank intermittently since installation.


Anyway, Monday I went to fuel, and filled both tanks with diesel. When trying to leave the station, the truck would not start--it came close once but immediately died. I ended up bleeding the fuel filter as directed, and eventually got it started again. I never ran out of fuel. I was running on the aux tank at this time.


Yesterday, I drove about 450 miles, drawing from the aux tank, if it matters. With much of the trip behind me, I was entering a highway and suddenly the truck bucked and lost power, forcing me below 65 MPH. The SES light lit at this time. After some initial anxiety, I realized the truck was still running fine, but would not allow me to exceed 2000 RPM at any time. I continued driving about 70 miles to get home with no further problem, and maintained 65 MPH just fine. At some point I switched to the main (stock) fuel tank, but this had no immediate or noticeable effect on the problem.


At home, I shut off the truck and then later started it again, only to find the SES light still lit. I tried again in the morning, with the light still lit, and called my dealer for an appointment. When I left for the dealer (70 miles distant), the SES light was out, and the truck operated normally and at all engine speeds.


The dealer pulled the following code history: 1093 and 1094. The service notes also indicate "...build good pressure at this time, also checked draw of fuel filter. OK at this time." I didn't speak directly to the tech, but the writer told me that all seemed well, and they weren't sure what had caused the code. I left with my truck and drove home with no problems. This is where it stands now.


Anyone out there have any input on this issue? Anyone experienced the same thing at all? I have a long trip scheduled at the end of October and don't relish this happening when I'm towing a 5th wheel.


Thanks for listening.


Tim

Tim,


Who made your tank? When you switched tanks was this with a switch or did it do it automatically? Have you done anything else to the fuel system or just added the tank?


Chuck

The tank was made by American Tank and Toolbox. It's a 45-gallon aux tank with an electric valve that is controlled by a dash-mounted switch. The valve is installed inside the frame, where it is spliced into the stock fuel lines. This was the only change to my fuel system, and I did it back in April. I have switched back and forth a number of times since.

It sounds as if something got stuck in the line and finally passed thru. Personally, I'd change the fuel filter since you have enough time on the second tank now. Before you toss it though, cut it open and see what it looks like inside. I'm not a tech so I can't comment on the codes. Hope this helps.

Where you at WOT when the light came on. because what happened was your truck went into limp mode. why it did is beyond me but your truck has a feature that prevents you from damaging your truck but will let you drive home OK. it is called limp mode. it will not let you past 2000 rpms. so i would bet something happened in your tranny.

Do you have a juice and attitude?

I have had the same issue where it won't go past 2000rpm and holds at 65mph. I did not get an SES light however.


I talked to Aaron at edge and he mentioned that other edge users have had the same issue. Both times have been fixed by a restart. Perhaps it is a truck issue more then a edge issue. It seems to be some kind of limp home mode. Edge can't really give any more answers because there truck doesn't have this problem.


*** edit- dmaxsnoopy beat me to it. http://www.dieselplace.com/forum/smileys/Embarrased.gifEdited by: Max Power

I understand about the limp mode, and understand that my engine was reacting properly in that capacity. The real question is why did it happen in the first place? If there were a real problem, which might have triggered limp mode, why would it automatically reset the next morning?


It's apparent to me that some non-event triggered this. It's running fine now, but for how long? Forever, perhaps. But maybe this will happen again. I can understand a fuel line blockage or temporary starvation issue, but why should this start the limp mode? I guess next time it happens (if) I'll pull over somewhere and let the truck rest a while and see if I can get it to reset again. But I hope it doesn't happen again.


BTW, my engine is stock--no juice/attitude or any other modifications beyond the aux tank.


Thanks for the help so far. I'm hoping someone can help me with the tec codes and shed some light on what they might mean.

Should be more info (characters/letter) for those codes. Only thing I can find is U1093/4 generic, which indicates "loss of serial communication to class 2 devices". If that's true, it explains limp, but it could be caused by a loose SP102 connector or a grounding out of the class 2 data line damn near anywhere or in any of the controllers. Maybe a fluke, too. Dmaxallitech?