The other day I was driving home and my Dmax would defuel as soon as it hit 2000 rpms. It did not log any codes or check engine lights, nor was it hot all was normal. I even had the factory/ stock tune installed.

I shut the truck off and started it again and all was well. The next morning I went on a 500 mile trip and all was fine. It has not happened again.

Anybody have a clue what' up?:help:

What were you using to read the codes? Sure sounds like a 1093. Lots of programmers won't read the codes properly for some reason.

I was using my Predator. What is a 1093 code?

I may be totally off base but I had the same problem on my 05 3500 at about 46,000 miles & it turned out to need all 8 injectors & rail replaced. It may run great for, like you say, 500 miles. Again it may happen 20 times in a row. It may be days. But, when it came down to it, thats what fixed it. You can run fine up to 1950 rpm but get to 2000 & its trouble. I can get more info on my experiance to you if you want it. I hope this helps.

More info please I have 30,000 miles on the truck and getting ready for a trip with my 5er and boat. I don't want to get stranded. Do you take it to the dealer for trouble shooting? Did this happen more than once? What ever you have please send on.

Thanks:)

Wouldn't a Tech II or OnStar be able to detect why it limped??

remove your tune and aftermarket parts and take it in. tell them about the limp mode.. have them check the injector harness and check the balance rates on the injectors.

if you are taking a trip soon then don't take chances and have it looked at.

Wouldn't a Tech II or OnStar be able to detect why it limped??

OnStar cannot diagnose codes like 1093's. They can look at ABS system, Airbags and some real general stuff. No detailed engine analysis is done with OnStar.

Tried it twice when I knew it was in 1903's (thinking...so they could have a record of it) and they said it was fine according to thier scans...but did ask if I wanted roadside called.

May be a bit legthy because it was over a period of time but I will try to keep it brief. I was in San Antonio, TX & I came out of a construction area going about 20 MPH. I throtled up to get on down the road & it kinda smothered down. I thought it was water in the fuel. I worked & worked with the fuel petal to get out of the six lane traffic & it just wouldn't take the fuel. Pulled over, bled the fuel filter, started it back & fine ... untill about 1/4 mile it did the same thing. I eased out of it & it strated pulling again. I played with it & as long as I kept the throtle to a minimum it would go. Trouble was, it needed to get up past 2000 rpm to shift, up hill, etc. I stopped outside San Antonio & bled the fuel filter again. It done fine for a while, then smothered down again. I found out as long as I kept it under 2000 rpm, it would go. Went to Houston to drop a little load. We got a hotel nearby & spent the night while I bled the filter again. Next morning I bled it again. It done ok for a few miles then it started again. I bled the filter again. Ran good for a while then again it would not run above 2000 rpm. I stopped in Livingston, TX at Chev dealership & had them change the fuel filter for $135. It did fine for a few miles then smothered down again. It was Friday so, I decided I would keep it under 2000 rpm (65mph) & do the best I could to get it home, to get in a local dealership incase it took a few days I wouldnt be stuck in a hotel for several days. Got home somewhat ok at 65 mph with exception of getting up hills & passing even slower vehicles. Monday morning I took it to my local dealer & nothing happend but they seen a couple of codes showing the egr valve & something else. They also changed the fuel filter again. Worked fine till I was almost home. Same thing ... smothered down over 2000 rpm. Tuesday Took it back to them & nothing. It run fine. We drove for 50 miles or so around town & on the hwy. Still would not cut out. They kept it & said it needed a software update. They did that. Picked it up & ran good ... for a while. Done it again. Took it back Wednesday. Still wouldn't act up. Went & got the trailer. Pulled the trailer for a 40 miles or so. Took the man back to the Chev dealership & let him out ... down it went again. I took it back & they seen it was indeed doing what I said. They kept it for three weeks. Talked to GM & they couldnt figure it out. They finally decided to replace all 8 injectors & the rail. Other things they considered was draining the fuel tank, changing the fuel pump etc. All kinds of stuff. They kept my truck that I make a living with, down for 28 days, knowing all along that they were having these injector problems out of these 05 LLY's. I fussed & cussed & thru fits & done everything I knew to do to get them to make the situation right because they continually held my truck unnecessarily, while they continually made excuse's & ... well I wont get in to that. Finally 8 new injectors & a new rail fixed it. Good thing I didn't stay in that hotel in Livingston TX till they figured it out. Hope this helps.

Youre right...that was a little long winded. Anyways:

Do you have an aftermarket exhaust? That could give the egr code before the update.

...after all that I think it was the fuel pressure regulator, which is in the Drivers side fuel rail. It would have gotten replaced as a complete unit with the rail. They can replace just the FPRV now. Now you wont know what actually fixed the trouble. Money is on the FPRV. Mine didnt give a CEL light.

JMHO....

My truck is completely stock. I really don't remember if I got a CEL or not. You may very well be right. It could have been the FPRV, honestly, I really couldn't say.
I appreciate your input. I have been here for only a few weeks but the people here are so very helpful & I have really enjoyed reading the posts. I am really learning alot. I appreciate everyone's input & I enjoy helping when I can. I hope all our feedback has helped SeaWizzard.