ISX Cummins running crappy...I think ?

If I could, I'd pull the EGR system off my truck and throw it over the fence! I've heard there's a big difference between the jakes on an EGR and non-EGR Cummins, so I guess the loss in mpg and the higher cost and chance of repairs is a trade-off.

When my EGR valve needs replacing, I hope I've figured out how to braze that sucker shut and put it right back in the hole. Defeating the EGR will normally give you about .5 to .75 more mpg, and I think the only real purpose to having it is to "say" it will run cleaner.

Too bad about your problems, have you tried having it dyno'd somewhere that can actually fix things? It seems like they'd be able to tell more of what's going on if they were plugged into it and running under a load.

Best to you, and thanks for the heads up about Central Power - I hope they starve. Did you keep your old parts? Sounds like you had a perfectly good turbo, and it's yours to keep you know (unless there was a core and it doesn't sound like it at that price). I'd throw a fit and stomp all over their toes if they don't do something about that - heck, I'd make them eat their words and their bill - or die trying for that price.

 

Is anyone concerned about unplugging the EGR valve and causing damage to the Turbo?
I read in another post one guys argument about this.
Getting new 3k turbo installed and was thinking about unplugging EGR but don't want to lose a turbo prematurely .

 

its very possible thats its a programming issue with the ecm, did you buy the truck used-it could have been a fleet truck, i see this alot at the dealer that i work for, people buy used trucks-not saying thats wrong, but thye ar estill set up for what the fllet had and the customer is pssed cause it only does 35...lol, have a dealer look at it again, if you need help let me know, i'll do what i can for ya.

 

I agree with the weird programming, mine has had it's quirks - although it's been a great truck over the last year and change that I've had it.

It was a Raven truck (Jacksonville, FL) and I'd heard from drivers that their shop and service program takes good care of their equipment. I've seen the results of that so far. The ECM programming isn't too bad, and I've been afraid to change anything so that I could get a good baseline mpg figure from it first.

The most annoying issue I have is that there is an odd speed limit setting on 8th L (13 speed). The ECM will lock it down most of the time at 60mph (about 1600rpm) in 8th Low - which is really 12th - and my 2nd to top gear. If I have to come out of the big hole climbing or passing, I'm screwed! I can actually rev 11th high enough to skip 12th. To top that off, there are times when it will grab 12th on a downhill in the jakes, and I have to clutch to get it released into 13 - the throttle won't let it rev any to disengage and float the gear. This has got to be an error, and one of these days I'll have someone look at it.

Other than that - it's locked down to 475HP and 1,650ft/lbs which is strong enough for anything I'm doing right now. It's also speed limited at 70mph, but that's not a bad thing, because I usually only run 70 tops - and my mpg really suffers at that speed thanks to running about 1,600rpm.

I'd recommend that our friend having trouble should have the electronics checked out, now that they've played with the hard parts long enough to goof up. Good luck with it, and keep us posted - any of us might be next!

 

I used to work at a Cummins shop and our motto was "If the motor is red it needs a head"

 

Tell that to the people that haven't seen a shop in 1,200,000 miles - ummm - repair shops see the broken stuff......

Nice outlook you had - I guess I could avoid that shop completely - where was it again?

 

Where do you work now...the T/A?.....

 

I have the same thing going on with the shifting and inconsistantcies in power the other day I was coming out of wva on 35 coolant temp climbs to 205 but won't come down get into southern ohio stop at mc d's shut motor off come out turn key on for a couple of minutes go around unplug egr knocked 15 degress off coolant temp and it goes through the first 5 gears so much smoother and does'nt smoke near as much as it did before

 

I'm not concerned about unplugging the EGR and causing a problem with the turbo. I have had my ISX's EGR unplugged for 150,000 + miles now. Not a single problem. The EGR is totally separate item from turbo so cannot see how that would cause a problem. The only problems I have had since the unplug had nothing to do with turbo or EGR. If you do the unplug, do it on a cold engine. Turn on the key without starting and leave it on for 15-30 seconds to close the EGR valve for starting. Then unplug the LOWER 6 o'clock position plug that unplugs towards the engine. Tape off the plug to keep out moisture. Then go about your business.

As to the benefits.... my oil now doesn't even start getting darker until almost 10,000 miles. My metal wear numbers are lower according to the used oil analysis. The last 3 mpg calculations pump to pump have been 7.8, 7.2, and 7.7. (average fillup of 160 gallons of fuel). Running variable weight loads up to 45,000lb in the box, combination interstate and two lane roads and rolling hills. This is in a '06 International 9400i pulling a dry box.

 

Hello;
A tip you may try. Remove air horn on left side of engine at intake,remove elbow going inside of hour glass shaped part.Cut off elbow and weld in plug and reinstall parts.Cuts off restrictiction, increases fuel mileage and eliminates headaaches. This prproceedure not really legal, but cheap and nobody knows egr eliminted. You will gain at least a gear plus. Let me know your outcome with this Please.