[Flintfarming]

Alright, someone help me figure this out.stock G56 swapped 06 cummins. So I bought the truck a little over a year ago. Truck smokes white ONLY under light to medium load between 1700 and 2500 rpm. This rpm range also seems to be low on power. Snappy bottom end pulls good after 2500 rpm (100hp single tune tuned it hp tuners) but struggles to hold speed going up a hill or something only in that rpm range. Checked turbo for leaked, dry. So I put a new set of injectors in. Still did it, took injectors back out and tested, all good. Idles smooth with no smoke. Put new tubes in the second time I put the injectors in, no change. So next I swapped fca, rail relief valve, map sensor, rail presser sensor, intake pressure sensor, all fuel and air related sensors and valves I could think of out of my 05 which runs flawlessly and made no change. I then ran some logs with hp tuners. Rail pressure desired vs actually boost all are good, I did notice the fueling on each cylinder would have the normal slight deviations and after I got into the rpm range where it was smoking they would all 0 out, not sure what to make of that. Ecm? So with almost 300k I tore the engine apart, which was in great shape, cylinders were glazed but no scuffing to speak of, valves and seats looked good etc. regardless I sent the head out and honed cylinders, fresh rings and rolled in a set of bearings and the damn thing runs exactly the same as when I bought it. Can someone help me out?

 

[rghavana]

Any codes ?
White smoke fuel or coolant?
How was manual swap done ?
ECM programed to manual trans ?
what happens stock tune?
Trans/ t-case wiring properly dealt with?

 

[Flintfarming]

Any codes ?
White smoke fuel or coolant?
How was manual swap done ?
ECM programed to manual trans ?
what happens stock tune?
Trans/ t-case wiring properly dealt with?

No codes, no coolant loss. Ecm is flashed for manual trans and does it on stock file and with tune. The wiring for the auto is zipped tied up and out of the way, that’s it though.

 

[steve05ram360]

Change the cam & crank sensors, use cummins only parts, they are cheap...

 

[krs]

Yes like Steve said.
Many of these parts need to be Cummins. There is so much junk from the parts stores etc in this department that doesn't work out of the box

 

[steve05ram360]

Whats the status on the cp3? Did you swap it from the other truck?

Can you share a fresh log file of the stock tune? Would need be a one where you take a route the has varying load on it where you can be using cruise and if possible, the problem shows up and goes away with the load. You can mark the event by canceling cruise and push in the clutch so rpms go to idle...

On the cam & crank sensors, as they age the pulse width of the signal off them will start to shorten in width which will have an effect of advancing the timing. No idea how long it takes for this to start having an impact on engine performance, i swapped mine with ~450k on it and my tune was off enough that i havd to retune it.

Another thought just came to mind... The pistons, are they correct for the injectors you used?

Since your tuning it, create a debug tune where the rail pressure & timing is more consistent thru the load ranges that are causing this issue and see if the problem repeats.