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Question on smoke output - joed2323 - 11-04-2016
Cm2250, 2012,
Truck has repeated frequent Regen issues, been on going for awhile
So looking at the codes,
first thing I did was remove the lower exhaust pipe below the doc, and the intercooler intake pipe from turbo fired truck up at a idle, and nothing but a oily/wet smoke shot out the exhaust piping/doc, it smoked up the whole garage.... I could wipe my fingers in the oily crap it spit out, or puked out warming up...
I didn't smell any diesel fuel, it didn't burn the eyes, but lots of black smoke shot out the exhaust pipe.
5 mins or so I bolted the piping back together and ran a few tests.
First one was, the fuel pressure test. The truck failed it miserably, it dropped like a rock from 29,989 to easily under 20,000 in like 15secs... Numerous times.
Did the one cyl cutout test, and all injectors sounded decent, motor didn't die out.
I replaced the fuel rail check valve. And it held fuel pressure after replacing the check valve.
My question is, once the motor warmed up, that black smoke quit blowing out the exhaust, but at a snap of throttle it still blew black smoke out (not as bad) where could all that black smoke be coming from??? Obviously this is contributing to all the excessive frequent regen codes..
The turbo is orginal, but the turbine wheel has play, im thinking it could be coming from the turbo or leaky valve guide seals, once motor warms up it doesnt piss oil out? Oil consumption isnt overly obsessive
Once the motor warmed up it quit smoking like a whor@
But have has repeated issues with this truck, I assumed at first it was a injector issue and over fueling or dumpin fuel but I had the exhaust pipe back off after the motor warmed up and it seemed like she quit pissin black smoke/wet moisture
Literally when I first fired up the truck with that bottom doc exhaust pipe off, It spit out a huge gulp black sooty oil/watery mixture... I had my head near it and it did not burn my eyes so my assumption of over fueling was wrong at first with the drop of fuel rail pressure at start...
Replaced that check valve and it fixed the drop of fuel rail pressure. It still doesnt explain the "high smoke output"
RE: Question on smoke output - Rawze - 11-05-2016
(11-04-2016 )joed2323 Wrote: Cm2250, 2012,
Truck has repeated frequent Regen issues, been on going for awhile
So looking at the codes,
first thing I did was remove the lower exhaust pipe below the doc, and the intercooler intake pipe from turbo fired truck up at a idle, and nothing but a oily/wet smoke shot out the exhaust piping/doc, it smoked up the whole garage.... I could wipe my fingers in the oily crap it spit out, or puked out warming up...
I didn't smell any diesel fuel, it didn't burn the eyes, but lots of black smoke shot out the exhaust pipe.
5 mins or so I bolted the piping back together and ran a few tests.
First one was, the fuel pressure test. The truck failed it miserably, it dropped like a rock from 29,989 to easily under 20,000 in like 15secs... Numerous times.
Did the one cyl cutout test, and all injectors sounded decent, motor didn't die out.
I replaced the fuel rail check valve. And it held fuel pressure after replacing the check valve.
My question is, once the motor warmed up, that black smoke quit blowing out the exhaust, but at a snap of throttle it still blew black smoke out (not as bad) where could all that black smoke be coming from??? Obviously this is contributing to all the excessive frequent regen codes..
The turbo is orginal, but the turbine wheel has play, im thinking it could be coming from the turbo or leaky valve guide seals, once motor warms up it doesnt piss oil out? Oil consumption isnt overly obsessive
Once the motor warmed up it quit smoking like a whor@
But have has repeated issues with this truck, I assumed at first it was a injector issue and over fueling or dumpin fuel but I had the exhaust pipe back off after the motor warmed up and it seemed like she quit pissin black smoke/wet moisture
Literally when I first fired up the truck with that bottom doc exhaust pipe off, It spit out a huge gulp black sooty oil/watery mixture... I had my head near it and it did not burn my eyes so my assumption of over fueling was wrong at first with the drop of fuel rail pressure at start...
Replaced that check valve and it fixed the drop of fuel rail pressure. It still doesnt explain the "high smoke output"
* The turbo is supposed to have up to 0.045" side-play in the turbine, and you can definitely feel it, so it is likely normal. I would not be so quick to blame the turbo without pulling the actuator off and giving it an inspection, but it has to be re-calibrated properly as you re-install it (I.E. don't pull it off unless you have Insite handy and can re-calibrate it). That is what OEM shops do. they are quick to blame a turbo and waste your money in the process.
Have you done an EGR tune-up on it throughly? and replaced all the sensors? -- It sounds like it is getting too much EGR into the intake because a sensor is reading wrong or the EGR valve is not operating correctly.
MAKE SURE you don't have an after-market EGR cooler or CAC unit on it like Duralite, etc... They are notorious for being problematic and restrictive and causing excess soot problems, and air flow restrictions.
The CM2250's are notorious for over-boosting and also making a bit of black smoke from the factory when you romp on the accelerator, especially when they are warming up. The DOC/DPF keep it from comming out the exhaust and most of all the soot goes right into the EGR and into the oil pan, slowly destroying the engine. it is quite normal, so If you don't plan on installing MM-2 in it,.. get a bypass filter on that thing ASAP while your at it.!
The wet watery substance,.. unless your loosing coolant (or it smalls like coolant) is likely just condensation. They put out a LOT of condensation when they crank up if they are not warmed up yet. It is an engine. -- And YES,... This contributes towards clogging up the DPF can over time. Combine that and someone romping the fuel pedal (or driving it before it is warmed up) and you got a recipe for DPF problems all the time there for sure.
The CM2250's are notorious for the valve guide seals leaking and needing replacing. That is what you should be looking at if the exhaust has oil in it,.. this will KILL the DOC/DPF can and keep them clogged up all the time/face plug them repeatedly. The turbo and exhaust manifold needs to be pulled off and and the exhaust valves inspect for wet oil on the stems. If your getting oil in the exhaust. The turbo needs to be inspected for this problem too, but it can also be soot-packed and worn out rings that have caused excess liner wear in the cylinders too.
REPLACE the IMAP and Exhaust BP sensors if they are more than 100k miles old.
CKECK the engine for boost and exhaust leaks and pressure test the engine to ensure the CAC, Intake, EGR, etc. on the engine for air and exhaust are not leaky.
Pressurize the coolant system and let it sit overnight and check for external leaks,.. and also check the back side of the EGR cooler to see if it is getting wet with coolant as well by removing the pipe on the back side of it and looking inside it with a mirror and flashlight.
=========
And as well, if your going to keep the emissions system on it and running...
I suggest -- DO A THOROUGH EGR TUNE-UP. Check the entire EGR system and clean it out thoroughly and replace old sensors. Replace the Delta-P sensor and clean its feed ports out too. Clean out and make sure the EGR valve is in good operation. A clean healthy engine needs clean healthy EGR components and clean, non-restrictive piping to work properly.
GET A BYPASS FILTER ON THE OIL SYSTEM ASAP and keep that soot out of the oil and eating up your engine!. ALL these newer egr engines are NOTORIOUS for carbon and soot packing via the oil and destroying the liners and piston rings prematurely. if ANYONE wants their engine to last more than 400k miles and not have excessive engine wear, atc... The engine needs something to keep the soot out of it. It is a very serious issue and everyone seems to take it for granted then complain when everything is worn out prematurely.
Ensure the NOX sensors are not too old. The one on the back side of the turbo likes to reads incorrectly after 200k miles or so and cause the EGR to be too high into the intake, making for excess black smoke long before they give and kind of fault. The ones mounted on the emissions system make it use too much DEF fluid, and also cause other problems.
RE: Question on smoke output - joed2323 - 11-11-2016
Thanks rawze.
Yes this motor, I did a thorough egr tuneup. Replaced imap,egp,egr diff, egr temp sensors, pulled egr valve off and completely cleaned all the soot out.
A guy before me replaced leaky exhaust mani gaskets and leaky exhaust bellow but he didn't check for the valve guide seals leaking, yes I know, why didn't he look for that. So I feel regardless, any motor that hasn't had the updated new valve guide seals installed, they should be replaced for piece of mind and the valves can be adjusted as well, all in one shot. Rules out valve guide seals leaking down the road
I did not know or have ever heard of excess boost issues with the cm2250s, that is good to know. What causes over boosting? Just faulty sensors or something within the turbo components?
Also, on pulling the pipe off the egr cooler, seems like lots of moisture and soot settle in at that pipe after the egr cooler almost having a person believe their is excess coolant/soot/oily buildup upon the engine warming up and burning that crap out of the egr piping...
RE: Question on smoke output - Rawze - 11-12-2016
(11-11-2016 )joed2323 Wrote: Thanks rawze.
...
I did not know or have ever heard of excess boost issues with the cm2250s, that is good to know. What causes over boosting? Just faulty sensors or something within the turbo components?
...
It is called terrible factory programming. Any slight imbalance or restriction in the exhaust or EGR components, especially during engine warm-up, and the ECM ramps up the turbo too high to try to compensate it.
Here is a video of one that has gotten so severe it is destroying the turbo...
https://youtu.be/huZXZnoNfrE
THIS ABSOLUTE MORON of a mechanic is so incredibly clueless it is not funny! -- and so are the people who commented on this video! -- WHAT a SHAME!@.
By the way,..the engine changed operating modes right at the very end of the video,you can hear it. It had nothing much whatsoever do do with what he was doing to it, other than the fact that it was warming up and jumped out of cold amb./ rapid warmup mode.
The engine is cold (below 140 F) it uses the turbo and over-spools it to put an internal load on the engine. It is the equivalent putting the engine under slight load to warm it up faster. This internal load also makes the engine and valve train quieter (cold diesel engines have noisy valve clatter while warming up otherwise). -- HIS PARTICULAR PROBLEM!-- Other than he is completely clueless AND USING A F$#$KING PIPE PLIERS ON A TEST PORT FITTING, Is in fact that the ECM is not seeing enough pressure at the intake manifold during warm-up. The turbo is WAAY OVER-BOOSTING, then "chuffing" (reversing direction rapidly). This is very very harmful to it. - it is most likely because the IMAP sensor (or EGR Delta-P or Exhaust manifold pressure sensor) is packed with soot and reading incorrectly.
This is one of my biggest complaints on how the turbo is programmed from the factory. They use what is known as "mass charge flow" (MCF) -- the sum of flow and pressure, and it wants always, a certain amount of it, regardless of the turbo position. this means if it is not seeing enough at the intake,.. The turbo will ramp up and choke off the exhaust, making for excess heat, flow restrictions, and a lot of other potential problems (like destroying turbochargers) to make the engine "see" with the IMAP and other sensors, what it want to.
This also means that if you have a huge crack in your charge air cooler, or have a restriction in EGR piping, leak, bad sensor, etc. - The turbo will simply ramp up higher and higher (to the point of damage if necessary) to compensate for the pressure loss,.. and your fuel mileage goes down, engine looses power, emissions system problems, etc. - And you are left scratching your head as to what is wrong. It is also why all of the bad deletes out there will cause repeating turbocharger failures, because the engine will see the blocking plates in the EGR system, or the valve closed, and try to make up for it by over-spooling the turbo out of control.
RE: Question on smoke output - Marajin - 11-12-2016
(11-12-2016 )Rawze Wrote: ...
It is also why bad deletes will cause repeating turbocharger failures, because the engine will see the blocking plates in the EGR system, or the valve closed, and try to make up for it by over-spooling the turbo out of control.
...
For everyone's curiosity who might have it, when someone maps the turbo properly during MM, it solves the factory programmed out-of-control scenario completely. It turns off mass flow compensation control and re-maps the turbo to run within a narrow window of pre-determined position ranges at every given rpm and fueling range throughout the engine. This means it will not go out of bounds, and only has limited compensation for small boost leaks, but not big ones. A larger boost leak will simply mean you get lower boost, and you can see it as a problem on your boost gauge. This is much safer for the engine instead of over-ramping the turbo to get what it wants. It also makes it much easier to troubleshoot fuel mileage related problems because it is not fighting for control any more. It simply goes somewhere and it is easy to see if it is providing proper boost or not. No need for guessing any more.
It is funny,... a LOT of trucks that have claims about turbo issues and associated turbo alarms, dealer says turbo is bad, etc. 70% of the time, after the OEM has deemed the trubo is bad, etc. and causing the emissions problems.
As soon as you MM it and it takes away the MC flow compensation, Magically it is fixed and operating for hundreds of thousands of more miles without issue.
I have seen it many times.
Tells me a lot of turbo's get replaced just because of a few incorrectly reading sensors. $4,000 dollars later and problem clears up slightly for a bit, then comes back in a few months. This is because the turbo when brand spanking new may be slightly more responsive and makes the sensors that are failing on the other side of the motor happy for a while.
After it brakes in though and settles after a few months, the sensors all go complain again, making turbo problems over and over. Those dumb bastards art the repair shops never give a second thought towards cleaning out the EGR pipes or replacing the other engine sensors first to see if the data the ecm is getting is valid. Their attitude is that if a turbo fixed it last time, the put another one on and go again. More money for them, and you are now broke and desperate, and cursing your engine.