'12 ISX15 demandate woes...

[NDISX15]

First time poster off and on lurker. Probably a victim of another bad tune. In my defense I did try to find another source but time and trust issues kinda hindered that and wasn't thinking about here at all ....but here we go. Truck actually did alright with the original emissions system and with insite i limped it as far along as I could before it was finally time to free up the exhaust and move along with life. Truck runs hills and highway mainly with a fair amount of offroad. ISX 15 450/1650 in a Pete 367Hwith 177k on the clock and well maintained, on the road more than it idles most days. Empty weight about 65k with trailer....105k-130k loaded on avg with some loads oversized. Some days a little lighter. Overheads are run yearly. VGT was kept and functions fine except 2 times where it "super spooled" (explain in a min). Engine and oil temps are the same as before. Never past 205 coolant and 230 oil even hard pulling 8% at max GVW. Its a low tier motor, so cal wise max i could get with incal would be 450/1750 but I've never changed it as the extra 100 ft lbs would hardly be noticed. Its never been a power house by any stretch of the imagination on its best day and could hardly get out of its own way....now it can get down the road but empty or loaded cant hold its own on even the smallest of hills/Knolls on the highway.. I dont know who made the delete or where it came from so I requested no increase in power/ torque level outside of what needed to be done to compensate for the recent diet. The cans were completely removed and straight piped, egr blocked with stainless. Unsure of gearing, but runs 65mph around 1475 RPM and 75 around 1750 RPM, boost is max about 32-34 psi when in the higher RPM (1500+) but for the most partunder heavy load 28-30 is about where it likes to stay. Fuel mileage/pressures and oil pressures are all same as before (best i can tell from gauges and fuel filter restriction gauge). Truck is normally kept in the 1500-1750-1800 range while cruising/pulling.

Things I've noticed thus far:

- power/pulling has dropped from pre diet. Even bobtail its rather noticeable. Honestly id have rather they just fixed/replaced the SCR and let me move on. Hills I used to climb and flats I used to run are slower and much more of a struggle. A lot more shifting than prior.

-turbo "super spooling".
Two times now since the diet, my boost has shot to 40ish psi. Once when splitting back to start a climb, when getting back into the throttle the turbo sounded like it shut too much and got back on the pedal and boost shot up then came back to reality. 2nd time it happened which is about 10 days later it happened when pulling out of the lot and just shifted into 2nd gear and got in the pedal and shot up and came back. Each time only lasted about 1-3 seconds, and not something I've been able to just repeat on demand.

-Oil consumption seems to have increased to roughly a gallon a week, but im also close to my PM service (which is being done Monday.)

Other than those few things, things seem to ok. Idles nice, good response, no vibrations or anything going down the road.....other than im about to strap a slow moving vehicle sign to the DOT bumper on the trailer. If more comes apparent ill add to the post. I have insite and c@lt3rm 4.17, I will get the tune downloaded out of the ecm for review when I get the chance. Im kinda save with these things, but not as savvy as I'd like to be.

[Rawze]

Pull the program out of it and e-mail it to me for a proper review. Assume its bad until you get it properly reviewed.

NEXT: you said it was straight piped ... you need to measure the resistance on can bus #2 to ensure it still reads 60-ohms with the truck shut off. - A lot of times, when people remove that stuffs, they unplug harnesses and it also removed the terminating resistor on can bus #2 inadvertently.. and later on, there are turbo and other issues with the engine.

[NDISX15]

I'll have to dig thru wiring diagrams to figure out the right location for ohm'ing that out when I get a chance. I should be able dig that up in insite, I think. Wouldnt that be one of those 3 (I think?) Pin triangle shaped end plugs?

[Rawze]

(09-18-2021 )NDISX15 Wrote:  I'll have to dig thru wiring diagrams to figure out the right location for ohm'ing that out when I get a chance. I should be able dig that up in insite, I think. Wouldnt that be one of those 3 (I think?) Pin triangle shaped end plugs?

the green and yellow wires on the 3-pin triangle looking connector... on the intake side of the engine wiring harness.

Its called the "Weather-Pack" connector.

[NDISX15]

Yep, exactly what I thought it was. Is that the one I need to check, or would there be one somewhere in the exhaust area by where the suffocation devices used to be?

[bwake]

(09-18-2021 )NDISX15 Wrote:  Yep, exactly what I thought it was. Is that the one I need to check, or would there be one somewhere in the exhaust area by where the suffocation devices used to be?

Check it where Rawze shows in his post. It'll check for the resistor in the turbo actuator as well as the one that is located in the DPF wiring harness. Each resistor is 120 ohms and your reading if correct should be 60 ohms total. If it reads 120, the DPF wiring harness most likely was removed along with the terminating resistor.

[NDISX15]

Sounds good, I will get a check on that. From a mid project/completed inspection when I picked the truck back up from the mech, the wiring harnesses were taped over and nicely tucked away and secured. Im 90% sure that the resistors are all in place as required.....BUT....theres still that 10%. Ill grab my volt/ohm meter in the am and swing by the truck (1 mile away) and take a couple readings on it and hopefully be able to get the tune downloaded and sent off for a peek. Im kinda itching to compare it to the original cal myself and see what all was changed.

[NDISX15]

So checked the resistance on the can 2, 60 ohms. Also reinspected all the hardware changes, nothing unnecessary unplugged and exhaust is about as straight shot as it can be to the stack considering how it needs to be ran. Replaced my IMAP sensor today during my service and ordered a new exhaust back pressure sensor and tube to replace the originals. 177k on the original and the IMAP was full clogged with soot. I think I've downloaded the diet file out of the ecm....but c4lt3rm is definitely not as user-friendly as I thought it would be. I saved something to my laptop.....but I may need a lil guidance if the file isn't the program from the ecm. Just for giggles jumped on insite to check codes. No codes,, not that im really surprised considering i have no idea what is or isn't suppressed.

Where should I send it to?

[Rawze]

(09-20-2021 )NDISX15 Wrote:  ...
a new exhaust back pressure sensor and tube to replace the originals.
...

most of the time the exhaust bp sensor circuit cloggs up where it runs thru the thermostat housing, and not the tube.

to check the entire circuit ... http://rawze.com/forums/showthread.php?t...5#pid65445