Cummins ISX CM871 Regen Temps Question

Anyways,..Just remove the components and clean them thoroughly. I tell most to get a toothbruch and a brush for clesning cups from wal=mart, then spray and clean the components with carb-choke cleaner as well as flushing the components out with water if they are really bad. Stay away from any liquids on the sensors tho, just brush them off dry or replace them. It is actsully not very difficult, and after the first time you do this, you will see clearly how easy it was, as well as the effects of how much better the engine runs. The actual teerm for what happens to these engines is called 'Congestive EGR Failure'.

BTW, I did not mention the EGR valve above for a reason. Defferent year model engines requires different processes in handling the EGR valve itself, because of design changes to the engines.

 

I would agree that your turbo is bad. What is the reading of exhaust backpressure when regen is active? Is the fan running all the time? The turbo will actually cause the percent load to be high. If you have any exhaust leaks between the engine and DPF assm it will also cause this issue. If you could upload a datalog of your regen I can graph it and most likely tell you what your issue is.

 

Also, remember when you are changing/cleaning the hydrocarbon injector to make sure you reset ALL in insite under advanced ECM data. You will be in for a world of problems if you don't. Temp #3 high but valid codes, melted DPF's, DOC face plugging and frequent regens.

 

i can tell epa has to many lines this an

 

Paccar makes a a flush for the egr cooler that works well, you have to make up your own adapter for the cummins egr cooler to flush it otherwise you have to remove it and soak it but it works! A tech at our shop had replaced a turbo twice on a truck that would not complete a regen, the turbo would start to spool up, load would increase, temp would only get to 500 deg. I went out reset the overhead. valves were ok but injectors were only about 30 in lbs not ok. reset them to spec and all was good again. truck had 375,000 miles on it. Might want set the overhead first.

 

I have also had injector check valves failed causing an issue w/ high engine load and low DOC inlet.

 

I'd remove it and clean it the old fashioned way, that crap your flushing into the engine is horrible. Cummins has done a pile of inframes in my area because of egr soot and what it does to rings/liners, and valves and valve seats (trucks under a yr old in some cases). I have a pic somewheres of a mountian of soot that i cleaned out of a faulty plugged/stuck closed egr valve and wow, you wouldnt believe how much crap goes thro your poor engine.

 

The paccar kit does not let anything get into your engine, you disconnect the inlet and outlet of the cooler, install adapters and valves. Flush w/ bio-degradable cleaner from paccar for 30 min, then 30min of tap water. Hook shop air to it to flush the water from the cooler. This flush was only done for a recall and if your engine was over 30% idle time.

 

All glory be to the mighty RAWZE! Thanks for your help today. RAWZE stopped in Dallas today on his way through and helped me do an EGR tune up. What we found was depressing to say the least.

Took off and cleaned the venturi, cross over tubes, Deta P sensor, air intake and temp sensor, IMAP sensor, and the doser injector. I have attached some before and after photos of the IMAP sensor and air intake temp sensor. As you can see they are completely clogged with carbon and were useless.

My doser injector was the worst RAWZE had ever seen! It was completely gone from inside the pipe and was unrecognizable. It means I have not done a regen on my truck in probably 250K miles or more when I thought I was doing them all this time. Hundreds of gallons of wasted fuel on failed regens because of the doser injector. All I can say is that if you have not done an EGR tune up on your truck in the last 200K miles you need to do it ASAP! One clogged sensor causes a cascade effect of secondary problems and you will chase your tail trying to figure it out. Every sensor and every passageway that carries EGR gasses needs to be removed and cleaned or replaced to do it properly. If you only do part of the system then something else in the system could still be causing you problems. Take the time and do it or you will be sorry later on. I am already sorry. I did my IFTA report for this quarter today also. 5.8 MPG for the last quarter!!! Mark my words I will have over 8 MPG on my next report!!

 

Found the problem today. Doser injector was completely gone. I will replace that tomorrow and do a forced regen. I will monitor the temps in Insite and post the results.