Cummins ISX CM871 Technical discussion

Hi guys. Does anyone worked deeply on cummins isx 2250 yet? I got my truck after overhaul at 420,000 miles back from dealer drove for 50,000 had no problems. Then truck started to misfire when worm ups. It only does when idle, if i will raise rpm on PTO its almost not noticible. When driving, it driver perfect. The Insight shows codes for cylinder 3 miss. Just changed the injector on cylinder 3, still does the same thing, and codes still for cylinder 3. I know those trucks have electric fuel injection system. I have read some threads on high pressure fuel pump? Also Ran a test for on insight for fuel rack test, and it failed due to Fuel system decay rate was excessive. i was thinking about Doser? Its original doser, now truck has 520,000 miles. Please help if anyone worked on similar issues before and what is the best way to diagnose this issue? Thanks

 

Very good information, thanks

 

Anyone have any ideas on 07 Intl 9400 with Cummings 450 isx. Unloaded drives fine. Loaded drives along fine then about 10-15 minutes in at about 65mph it loses power for a few seconds the end light comes up and then it regains its power. But does it repeatedly. Throws fault code 434. Loss of power when ignition is in on position. Been in 3 dealer shops burnim up labor hours and spent about 10000 tryim to get it right. Nobody can figure it out. They all say battery connection is good wires good ecm good egr already replaced a year ago. Any suggestions?

 

I've been away awhile, busy running this ISX and monitoring it's performance. Mine is a 2000 model, pre-emissions free-breathing one, and it is by all means, a good running one.

Pulls like a freight train, and I'm always 90K lbs. under permit.

Fuel consumption is average according to all information I have obtained, around 4.8 mpg this time of year.
It still has this issue of drooling oil (or possibly fuel) out the exhaust manifold ports when idling for any extended period over 10-15 minutes, which I have to do periodically to pump off loads of product running a PTO.

My last oil sample came back perfect, no elevated levels of fuel or any signs of wear, so I'm reluctantly ruling out leaky injectors. I replaced 2 of the 6 back 5 months ago, but I'm thinking about doing the other 4 just as an insurance policy. Not a guaranteed fix, as I've seen plenty of faulty reman and even new injectors come out of a box in my time. But, that's life nowadays.
All in all, it's performance is above my expectations, and I'm considering myself highly fortunate that it has a normal turbo and no EGR stuff attached to it.

I am using a couple of gallons of oil between my PM's as well...just changed it 3K miles ago, fresh oil, and I use about 25% Lucas Oil Stabilizer in it which I am a believer in, as it boosts the oil pressure by 2 lbs., and it just makes sense. My oil I believe, is going somewhere it shouldn't, as through the exhaust. I have to check the pressure side of the turbo/charge air tube for oil residue yet; been crazy busy and dark and cold any time I have a free minute to do anything other than operate this truck right now.

It idles lousy; sounds like it's running out of fuel every once in a while, sits there and sputters, skips, something. I am starting to lean towards a leaky injector, as the past couple weeks when I go to fire it up (hot, after sitting for a few minutes to a 1/2 hr.,) upon initial startup it almost seems to "hydro-lock" as if it had coolant in a cylinder, but that's definitely not the case...but could very well possibly fuel if I wasn't so lucky.

I am awaiting this past PM's oil sample report to determine what course of action I should take next.

Not disappointed in this motor at all, for what I paid for the truck and the overall condition, I am pleased with everything about it. Looking around at all these newer ones and all the horror stories involved, I'd be chapter 11 if I owned an EGR engine right now, having to service the customers I deal with in the petroleum business.

Just thought I'd shed some light on the subject. They're all great when they're running good, right?

 

lucas in an isx is questionnable,jmo.