Cummins ISX Smoking

Probably not the same problem, but maybe?

For the last month or so, I've been having heavy "whitish" smoke coming out the stacks when pulling a load up a grade, or when accelerating from a stop (i.e., scales). No coolant drop over that time. Also, no codes, so shop (it's a company truck) just shrugs their shoulders.

EGR valve has been replaced 3 times in the last 6 months, the last time 3 or so months ago. It seems like I might have lost a little power since this problem started, but not much, and that may just my thinking.

Truck is going into Cummins, I just talked to my shop manager, and I think he said something about it being a "gps? gds?" problem, which he said was a big deal. What is that? If it is a gps problem, it must be a different kind of gps than the one I use which routes me under 12'9" bridges, right?

Anyone have any ideas on what could be the problem?

 

Mine was smoking real bad and smoke when I climbed hills or under throttle. Then eventially I got an intermittant check engine light. then a solid light.

Turns out it was regen problems. There is a fuel diverter valve that goes bad. It diverts extra fuel when its suppose to regenerate and doesn't shut off, hence smoke.

It's on the drivers side, lower block in the middle. It's about 1" red cylinder by 2-3" long and has a pluggin. At least that's where the mechanic was reaching.

 

Thats pry the Aftertreatment fuel shut off valve. They will start to stick, usually just take them out and clean them real good and put it back in. If the code is active it wont let it go into regen

 

EGR probably shot, but new turbo just because of actuator? Replaced the actuator on my Holset Turbo for a mere fraction of replacing the whole turbo. Been a year, but I think the actuator was around $175. I haven't done it, but a few guys around here, when they replaced the EGR, they welded/brazed it shut before installation. Same effect as unplugging the EGR without the CEL and codes. Then future EGR problems and replacing are eliminated. I unplugged mine. I like the .8 mpg average increase and cleaner oil and engine. I did that approximately 170,000 miles ago and have had no regrets.

 

That's it. He replaced it instead of cleaning. Under warranty.

 

Turned out it was the "DPR" filter? Whatever, cost the company $3200 plus, out of warranty. Wonder if it would have been any less expensive had they listened to me in the first place?

More power now, too.

 

I kinda glad someone else has this problem. I've been having the same thing with my isx, told and had complete inframe done. Here's the story.

Whilst my trusty beast was working her little heart out she started smoking. So I take her to the dealership I got her from. As the oil sample report stated that there was excessive soot and metal in oil. Well to make a long story short I ended up with an inframe finding only one ring broke, but the cams flaking, not good. After changing everything but the block, heads, crank and injectors, LO AND BEHOLD I STILL HAVE SMOKING MACHINE.

Upon opening her up they found number 2 and 3 cylinders with excessive soot in them. So I firmly believe that the injectors are at fault and would probably give better fuel economy, BUT seeing that the computer doesn't pick up this little fault, mechanics or technicians if you will refuse to acknowledge this item. which to me shows that the people are AFRAID OF CUMMINS. My next step is the injectors.

So if anyone else has hasd problems with this and has had it fixed, PLEASE LET ME KNOW.

 

possibly this tip can help you. i read the manual a lot and its not the injectors. you need to check in the morning when the actuators is cold. theres two that synchronizer(timing) that are in the sides n you need to check and the dosifier(fueling).in the middle you need to find a male plug(deucth) and try it with a multimeter the Resistance OHM cold fueling actuator( 0.54 -1.07)the 0* to 130* and( 0.67-1.20) 100*to 200* timing actuator( 0.87-1.73) the 0*130* (1.10-1.97 )100* to 200*thats what it should be, if it has less or more then their wrong. this is doing it if you dont have insite. i dont know if your motor when its idle sounds like its sneezing or in the morning it doesnt sound smooth but when it heats up it gets better

 

I have been told that the smoke is simply from the diesel thats injected into the DPF when it regins. I keep having problems with low manifold pressure. one minute its ok and the next its low and losing pulling power.

 

I have a isx cummins and when the egr valve went out it would pour out the black smoke like a freight train all the time while under a load. It was sluggish on power but did ok once it was high rpm's.