[Laray]

I was pulling my 10,000 lb. 5th wheel trailer a few days ago. We were about 1 1/2 hrs in the trip when I noticed a loss of pulling power. While going down a hill, I let off the accelerator. Near the bottom of the hill I tried to speed up but found I had no power. The truck slowed to about 25 to 30. I managed to get to the top of the not so steep hill. I stopped and turned off the truck. When I restarted, I had full power. This happened 4 more times in the next 150 miles (3 hrs). I have plans to replace the fuel filter. Codes show P0009, P0380 and P1781. Also I can't seem to find a repair manual for the Duramax. Help

 

[05_LLY]

What are you using to read codes? sounds to me like it is p1093ing which is low fuel rail psi caused by either big power programs, or a dirty fuel filter! how old is the fuel filter how many miles, this is the most common cause of a problem like your stating, especially while towing up and down hills?

Later
Caleb

 

[fishing3x4]

I experienced the same thing twice this week while pulling my 10,000 lb camper. I have a 2001 totally stock, with 109000 miles. I had to pull off the interstate while pulling a hill, shut off the engine, wait a couple of minutes and then restart. I regained full power after the restart. In both cases I was pulling a hill and the truck downshifted to try to maintain speed. Then it suddenly dropped to 2000 rpm and completely lost power, like an anchor was thrown out the back. It would not rev over 2000 rpm even when in neutral untill I shut it down and restarted. Once restarted it ran fine as long as I kept it from down shifting while pulling hills and it had plenty of power. It seems to have dropped into a limp home mode for some reason and set a code but I haven't had time to check what code was set. I recently changed my fuel filter and since it went into a limp home mode I do not suspect a filter issue. I recall this happening when it was brand new but I attributed it to high altitude at the time since I was at 9000 ft when it happened then. This time I was at less than 2000 ft when it happened. I am wondering if anyone else has had this problem and knows what could have caused it.

 

[ob_1jr]

Yeah, I would worry about it being a fuel filter. The P0380 is glow plug circuit A and the P1781 is the TCM requesting the MIL light to come on...You might have a tranny code, but you will need something like a Tech II to read those codes.

 

[duramax150]

i had the same thing happen it ended up being a bad mass air flow sensor it kept saying it was overboosting

 

[duramax150]

won't start

only start's with a small shot of starting fluid the runs fine, makes no sense to me

 

[SANCGCS]

Ether junky

 

[duramax150]

disregard my last reply, oops

 

[SilStk1]

I have a 2003 GMC C4500. Definitly the fuel filter, I was told by the dealer that it has to be changed every 7,000 miles on these trucks/ engines.

 

[NEO]

I was pulling my 10,000 lb. 5th wheel trailer a few days ago. We were about 1 1/2 hrs in the trip when I noticed a loss of pulling power. While going down a hill, I let off the accelerator. Near the bottom of the hill I tried to speed up but found I had no power. The truck slowed to about 25 to 30. I managed to get to the top of the not so steep hill. I stopped and turned off the truck. When I restarted, I had full power. This happened 4 more times in the next 150 miles (3 hrs). I have plans to replace the fuel filter. Codes show P0009, P0380 and P1781. Also I can't seem to find a repair manual for the Duramax. Help

I had the same issue pulling my trailer up hill loss of power "limp mode" Codes P0380 and P1781

did you figure out what the problem was?

P0380 is something to do with glow plugs:
I have yet to determin what my issue is but I plan to test the glow plugs today and if they are ok I gues I'll replace the glow plug module.

P1781 is 4x4 Switch Out of Self Test Range
also I have yet to figure out this one...

 

[NEO]

I experienced the same thing twice this week while pulling my 10,000 lb camper. I have a 2001 totally stock, with 109000 miles. I had to pull off the interstate while pulling a hill, shut off the engine, wait a couple of minutes and then restart. I regained full power after the restart. In both cases I was pulling a hill and the truck downshifted to try to maintain speed. Then it suddenly dropped to 2000 rpm and completely lost power, like an anchor was thrown out the back. It would not rev over 2000 rpm even when in neutral untill I shut it down and restarted. Once restarted it ran fine as long as I kept it from down shifting while pulling hills and it had plenty of power. It seems to have dropped into a limp home mode for some reason and set a code but I haven't had time to check what code was set. I recently changed my fuel filter and since it went into a limp home mode I do not suspect a filter issue. I recall this happening when it was brand new but I attributed it to high altitude at the time since I was at 9000 ft when it happened then. This time I was at less than 2000 ft when it happened. I am wondering if anyone else has had this problem and knows what could have caused it.

Did you check your codes? if so what were they?

 

[halbur12]

I just had the very same problem with my 06 duramax lbz.. Was wondering if anyone found what this was for sure.?

 

[lifteddirty]

It sounds like a plugged fuel filter, the engine will derate itself whenever it thinks that its going to do damage so thats probably where the loss of power came from.

 

[halbur12]

Ok I will check the fuel filter.. If that looks good I will bring it in to have the code ran.. Maybe its the mass air flow sensor they were talking about.. Thanks for the help!

 

[4darrell]

What have you found out?

 

[crashtke]

My father had this same thing happen on my truck before he sold it to me on a highway pull. Did a fluid and filter change and no issues yet.

 

[Gerald Dew]

help , got a chev 2004 3500 4x4 with a Duramax diesel V8 6.6 motor . my problem is , when the truck is sitting in neutral or park I can rev the motor , as soon as I place it into gear I have no power, the air filter has been changed and am using winter fuel . I just bought the truck and its as been running good , need help , thanks GD