vander

Greetings, hopefully someone can help with some information and/or ideas about the issue below. The truck is a 2007.5 6.7 3500 DRW auto, completely stock engine and drivetrain, 72,000 miles, very well maintained, used to tow a trailer weighing between 15-18k.

Twice in the past month, both times after the truck had been sitting for 8-10 days, I experienced a troubling startup issue. The truck started and fired after the normal delay (1-2 cranks), but there were several immediate problems - 1) even with the windows up and the doors closed, the turbo whistle was VERY loud, louder than I have ever heard it in normal operation. 2) the engine was rough, almost like it was running on less than 6 cylinders 3) it had no power, and I could not get it to rev above 1000-1200 rpms, just sitting in park. It labored to even get to 1000 rpms. Both times, I shut it off after 6-8 seconds of running like that, waited 10-15 seconds, and restarted it. Both times, it started and ran perfectly the second time. Neither time was a CEL code displayed, and the truck currently has no codes (using a generic OBDII code reader that has properly displayed correct codes on the truck in the past). The truck has only done this those two times after sitting unused for 8-10 days. Other startups, even after sitting for 3-4 days, have been normal. In the past the truck has sat for a month or more without problems. The truck has had no significant issues in its life so far, other than 3-4 engine emissions codes, and a small clogged emissions pipe about three years ago that I cleaned out successfully. Any ideas?

Thanks for any help!

mega-engr

Sounds like an emmisions related problem and the variable turbo maybe sticking, especially after sitting a while... The second start up gets things loose a bit it sounds. Take it out for a good run and cleaning. EB on Tow Haul and decelerations...

vander

Yeah, a sticking turbo was my theory as well. It could explain a lot - no boost, no hp, engine rough and shaking, lots of turbo noise, etc. Strangely enough, I drove it empty 400 miles on Saturday (empty, but at 80 mph on I-5, so it got a decent workout), then it mostly sat idle Sun and Mon, then it had the same startup issue again on Tuesday morning when I went to return. Tuesday morning I had to stop and restart it 3-4 times to get it to run normally, then it was fine. I towed an RV home (only 7k lbs) Tuesday 400 miles, so it got a little workout, but not a massive one. I use the EB often, and 100% time when towing. I fear I may need to have the turbo cleaned out, I need to do some research....... I am very aware of the soot issues these trucks have, the only previous issue I had was when I had to daily drive it for 2-3 months and I had to clean out a small emissions pipe that was clogged with soot. The past 4-5 months it has been used regularly for heavy towing, so that isn't the problem (daily driving under light load). I wonder if 72k miles of use has just clogged it up....

vander

It is surprising that it doesn't throw a code when it does that. As finicky as those engines are, throwing lots of emissions codes often when nothing it wrong, it is strange that 5-10 seconds of running like that doesn't trigger a CEL. The engine seems very unhappy when it is in that mode, so I have never cared to let it run like that for more than a handful of seconds. I wonder if I did let it run for 20, 30, 60 seconds if it would reveal a code. I probably won't try it.

mega-engr

I've had emmsions codes pop up even when it was running fine...This is why I chose to delete right away. It would not get better from there. Basically, you need to run with the EB on all the time, not just towing. I tend to think that the long drives at the high speeds is where things in the turbo are fairly stagnant movement wise and will load them up. Keep the EB on all the time to keep everything inside there moving and the soot moving on :-).

vander

Yeah, I run with EB on almost all the time, probably 80-90% of the time when just empty and 100% when towing. But my last dozen long tows and trips have unfortunately had lots of steady-state constant speed running. I guess I'll need to make a concious effort to vary my speed more often. My 400 mile trip Saturday was almost totally constant speed 75-80 mph cruising (LA to Sac) so perhaps that is why Tuesday morning it was so difficult to start. I'm hoping the 100k warranty covers a turbo cleaning, many things I read indicate that it does.

mega-engr

Let us know about the turbo cleaning!

vander

Well, two different dealers have told me that a clogged turbo is not covered under any extended (Cummins or emisions) warranty. Has anyone had any different luck or gotten any different answers? I am not certain if cleaning the turbo myself is an option, I will have to do some research. I am a very good mechanic, but I lack any mechanical or electrical tools for these trucks, all of my tools are either generic or for the race cars. If it is a generic thing, I can probably do it, but if it requires any special tools I may seek an independent shop. Time to do some more reading......

BigIron70

Normally P2262 will set if there is a turbo problem. If you never had turbo cleaned or replaced then it is time to have it cleaned at 72,000 miles. You are past due for EGR clean, EGR cooler cleaning, crankcase breather replace if not done already. Here is cleaning procedure, all can be completed in one day. If interested in having done PM me

vander

Thanks much! I have already done the full EGR and crankcase breather maintenance at 65k, and truck has been fine for the last 7500 miles or so since that maintenance. I will look over the turbo cleaning procedure and PM you if I have questions. Thanks!

vander

I have discovered a new piece of info about the rough startup issues I have been experiencing. This makes me think the problem is an electrical one and maybe not a sticky turbo. When I went to start the truck, I noticed that the exhaust brake switch light was on and stayed on when I started up the truck. My experience and understanding is that the exhaust brake should default to off. The rough startup, extremely loud turbo whistle and total lack of power could be explained by a faulty exhaust brake switch or controller. In the past, I was able to clear the problem by turning off and restarting the truck. This latest time, when I noticed the exhaust brake light staying on, it stayed on the first few times of stopping and restarting, and these first few times the truck restarted rough and horribly. The third or fourth time when I attempted to restart it, the light defaulted back to off, and the truck started perfectly normally.

Has anyone heard of any issues with an exhaust brake malfunctioning like this? I still realize that the turbo may be clogged and needs to be cleaned, and that is directly related to this issue somehow.

vander

I took the truck to my local dealer last week, and they looked into the problem. They did apply the most updated engine software, hoping that would solve the issue, unfortunately it didn't. They did discover that the truck, when it is having the issue, will run fine once moving and at highway speeds. It is only when stopped (in park and/or neutral) and when moving at low speeds that is will buck and surge and run rough, and the turbo will whistle and scream. So they think it is a problem with the torque converter or trans. At first they were telling me to just replace the entire trans (which includes the TC) for $5k+ or at least replace the TC ($900+), and I told them that for those prices I will just keep running the truck until it has a more definitive failure or throws a code of some sort. So they have the truck again and are continuing their diagnostics and are opening a case with Dodge. My guess is that it is a sensor or solenoid of some sort that is causing the issue, since it will run and shift just fine at higher speeds, and since an electrical reset (turning the key on and off) fixes it most of the time. If the trans and/or TC were bad, even the dealer tech agrees that it would likely be bad almost all of the time and wouldn't be so intermittent. Hopefully I will not need a new trans or TC. Anyone know how difficult those are to install yourself?