Intermittent boost loss

[Heavyhaulmark]

Some updated info.... I pulled out my old bullydog watchdog(not the tuner) and checked for inactive codes. I actually found 3 ACTIVE codes, but it's not trigger a light.

Code 2347: turbocharger compressor outlet temperature (calculated 0 - Data valid but above normal operating range - least severe level

Code 3385:intake manifold 1 temperature - data valid but below normal operating range - moderately severe level.

Code 2288: Turbocharger 1 speed - data valid but above normal operating range - least severe level.

There also 2 inactive codes

Code 1887 aftertreatment outlet NOx sensor circuit - voltage below normal or shorted to low source.

Code 3545 aftertreatment outlet NOx sensor - abnormal rate of change

While typing this I just noticed the code 2347 went inactive then active again.

[Chamberpains]

Is your truck emissions disabled in any way? It's very common for horrible deletes to suppress the check engine light from coming on to hide their shitte work. If so, you know what your problem is. Get the programming fixed. If it's not disabled in any way then you may have the wrong cal in the ECM like Mr. Hagg said. Look at the data plate on the valve cover and get the calibration code off of it and check if it matches the current calibration you have in the ECM.

Does the CEL (check engine light) cycle or come on when you 1st turn the key on? If not you have a faulty CEL circuit.

Those codes all trigger amber CEL and derate the engine. The fact your not seeing the CEL is a problem that needs to be fixed.

[Heavyhaulmark]

No alterations of any kind. Everything on the engine is stick or stock replacement. No tuners, upgraded manifolds etc etc. Check engine light comes on @ ignition, cycles then goes out. I know it works because occasionally I get a code for intake temperature when it's really cold out.

[Rawze]

signs point to turbo over-working itself.

start by pressurize the whole engine (front of turbo) to back of turbo/exhaust outlet to 30 psi and find the cac and other air/egr circuit leaks.

that or test CAC, then intake, and exhaust/egr.

maybe something wrong w turbo?

need re-calibrating? -- hanging up?


anywas, signs point towards air/boost problems.

air/egr-gas/exhaust related issues will throw codes down at the aftertreatment system.

ALSO. make sure your filters pass a flow-test.

and inspect for the infamous 'volcano' (ref: http://rawze.com/forums/showthread.php?t...07#pid1807 ) and inspect the SCR element for face buildup... that SCR canister element face should be clean as a whistle.

[Hammerhead]

(01-05-2020 )Heavyhaulmark Wrote:  I adjusted all the clamps on the turbo there were a couple I could tighten but not much. I changed the 3 main sensors that always seem to be recommended. Actuator is new/reman, it came already pre set and mounted on the turbo. I think the overhead was ran last year, but I'm not positive. Change the oil @ 15k or sooner. The emissions system from the egr cooler back to the stacks was completely dismantled cleaned tested and put back when the turbo was done. I think I changed the back pressure sensor.

I do what you do. I have a multi-axle HH unit and run around about 180k loaded, so we're talking the same thing.
If you still have the emissions system intact, you need to change your oil change intervals. You will carbon pack the $h!t out of that motor if you don't and prematurely destroy it!
The weights we pull, and the fuel we consume dictate a different maintenance cycle.
Get a bypass oil filter put on thing ASAP!
Change your oil at 250hrs! You will find this will be in the 8000mile range. Oil life is determined by contamination, not miles or lifecycle. The volume of fuel we consume means that even at 8000miles, we have contaminated our oil with combustion bypass residue with MORE contaminants than these hyper milers have at 18-19000miles like Rawze and the boys on here! The reason is simple, in 8000miles, we've burned more fuel than they do in 18-19k!
If you want to get any kind of life out of that motor, keep the contaminant levels LOW!

[JimT]

If you haven't done so already, register your engine ESN with Cummins Quickserve. Until you get an Inline adaptor and Insite you can use your watchdog to read the codes from the ECM then look up the codes and troubleshooting steps directly on the website.

Based on the codes listed, the intermittent loss of boost is because of the 2347 code and the automatic ECM response. However this is just a symptom. Rawze's suggestions mirror the info from Cummins (which you can lookup on the website). Possibly a leak somewhere in the air intake system, bad sensors (or wiring), or malfunctioning EGR valve.

My own experience: Back in the summer I started to get the same turbo temp codes. checked the intake system and found a massive leak from the small silicone elbow going to the air compressor. looked like someone went crazy with a cheese grater. I replaced that and the other 4 silicone boots and replaced a leaking exhaust bellow at the same time. problem went away. (the air compressor had been replaced 2 months earlier and the elbow appeared fine at that time)

[Heavyhaulmark]

So I finally had a day to look more closely at the situation. I changed the Intake manifold pressure sensor and turbo speed sensors. While I was working on the turbo speed sensor I somehow bumped the EGE pressure sensor and cracked the plug housing so it got replaced as well. I had a friend stop by and talk to me while I was working on all of this and he said he had the same code(2347) pop up and it was the sensor located on the compressor side of the turbo. I went to unplug the sensor and noticed the whole plug assembly on that sensor could spin almost freely, so it was replaced as well. Between the 4 sensors, I think everything is good. All codes cleared out and It ran fine up till the point a zip tie broke and the turbo speed sensor wire bumped the exhaust manifold...... I put the old turbo speed sensor back in temporarily and now I have the turbo cutting out again and code 2288 coming back.