Cummins ISX CM871 Technical discussion

sry, missed the post,...

I am not promoting these guys, but I can tell you I really like the Amzoil bypass filter I have on my truck. Its dirt simple and I got it for about 400 bucks + 350 to install it in portland,or at jubitz. My soot levels (when I still had EGR) went from 2.6-2.9 every 25k to 0.54 - 0.57. I change the filter every other oil change at 50k. the filter costs me $36 bucks, and is a simple screw-on type. I do not run synthetic, and still change my oil every 25-30k because I am just stubborn I suppose about not changing your oil.

 

Looks like I will be in Denver,CO the 26th, 27th, and/or maybe the 28th. I will be at the TA truckstop at I-270 exit 278, Quebec street. PM me if you want to meet up and BS a while,...Rawze

 

What 3 sensors? the IMAP, EGR Temp?, and Delta-P?,...The Delta-P needs replacing not cleaning every 250k miles.

Also, if your intake manifold was really dirty, then perhaps you need to remove and clean the EGR valve, especially if there was ever a coolant leak from the EGR cooler. Sometimes the actuator for it goes bad also, but it will usually always give alarms for it. The valve body itself has been known to stick open and not give alarms, so the only way to know for sure is to remove and check/clean it. That usually isn't a problem for about 500k miles tho if you never had a EGR cooler leak.

I need some details,...What kinda truck, freight, speeds driven, engine ISX CM871? I take it? truck model? what MPG you getting? the more detail, the better. You got a boost and/or a pyro gauge?

If its fuel mileage your looking for, then you will need to work at it. Yes, cleaning all the sensors on the intake and cleaning the intake itself helps, especially if they were really dirty, but there are a lot of other factors like a good CaC, CaC boots, the turbo itself, the DPF Hpa reading, the list is long. What you do is start with the cheapest stuff first. If your IMAP sensor was really bad, consider replacing it with a new one. Thats a cheap start, as well as check the CaC and boots for leaks/cracks.

 

that is definitely not all the good. You could ensure your EGR valve is not sticking and/or maybe the IMAP needs replacing. Also make sure your After-treatment injector is keeping the DPF below 3.0 hpa. Thats where I would look next if it were my truck.

177k miles, those systems shouldn't be in too bad a shape though. If you got really crappy tires on the truck and trailer that might be killing your fuel mileage, but not while your running empty/light. Are you idling a lot with it? that will make fuel mileage seem low too.