Bogging down - extreme smoke
Thread Starter
|
New User
Joined: Mar 2006
Posts: 2
Likes: 0
Bogging down - extreme smoke
First post on the forum but need some input on a recent problem. I have a '04 SD250 with the Diablo Predator installed. Great product - currently tuned to 65 HP setting. I started to experience "chugging" a while back, and the problem has consistently gotten worse. This happens on acceleration in the "mid range", such as going from 50 to 70 or so. Rarely does this happen off of the line. This "chugging" causes an extreme amount of smoke / soot on discharge, and sounds as if there are backfires within the engine. Are there any quick fixes to this? Any other users experience this type of problem? Thanks in advance.
Senior User
Joined: Mar 2005
Posts: 111
Likes: 0
From: columbus MS
You probably want to post this in the 6.0 forum.
Sounds like your turbo is surging. almost all programmers change the way the vanes in the work with the 6.0. What happens is the programmer moves the vanes in such a way that gives better WOT power. At mid range acceleration the vanes flow the exhaust to the turbine in such a way that it is not able to produce enough power to run the compressor. The compressor stalls, allowing the air to rush back out your intake. Now that the pressure has dropped between the compressor and the engine intake, the compressor raises the pressure again, but to rapidly because of the pressure void. The turbine then cannot provide enough power, so the compressor stalls, and the process continues. This can also be agitated by the vanes moving, when the ECM does not realize the turbo is in a stall/surge condition.
Now, how to fix it. If it does not do it when the programmer is off, then it is just the program. My SCMT does it on the econ mode, but works fine on the other modes. If the turbo does this with stock programming, then I would suspect one of the sensors (MAP or EBP, the latest flash eliminates the EBP) or the vanes sticking.
Sounds like your turbo is surging. almost all programmers change the way the vanes in the work with the 6.0. What happens is the programmer moves the vanes in such a way that gives better WOT power. At mid range acceleration the vanes flow the exhaust to the turbine in such a way that it is not able to produce enough power to run the compressor. The compressor stalls, allowing the air to rush back out your intake. Now that the pressure has dropped between the compressor and the engine intake, the compressor raises the pressure again, but to rapidly because of the pressure void. The turbine then cannot provide enough power, so the compressor stalls, and the process continues. This can also be agitated by the vanes moving, when the ECM does not realize the turbo is in a stall/surge condition.
Now, how to fix it. If it does not do it when the programmer is off, then it is just the program. My SCMT does it on the econ mode, but works fine on the other modes. If the turbo does this with stock programming, then I would suspect one of the sensors (MAP or EBP, the latest flash eliminates the EBP) or the vanes sticking.
Egr ??????????
Senior User
Joined: Mar 2005
Posts: 111
Likes: 0
From: columbus MS
Chad, good catch on the EGR, since it is also linked to how the turbo works (and the root of all evil). I would only use this for a diagnostic, since the ECM likes to have it hooked up.<O
</O
Does anyone know why some of these programmers do this in the intermediate mode besides just speculation?
</ODoes anyone know why some of these programmers do this in the intermediate mode besides just speculation?
Originally Posted by chadjones99
try disconnecting your EGR and see if that fix's it, it helped mine alot when it was doing that., off road use only you know (hahah)
Junior User
Joined: Apr 2005
Posts: 93
Likes: 0
From: Scotts Valley, CA
I had this before the latest recall and reflash. The EGR sensor (I think) was replaced. The problem is resolved. I think it's the same thing anyway. Happened around 1200 to 1400 RPMs...felt like it was choking...then big cloud of white/grayish smoke...then OK for 30 seconds...repeat....usually ocurred while accelerating...from a light or even off a coast...wasn't so much speed related as it was RPMs.
