Have no clue what's really wrong.

[Copper]

(10-18-2023 )Rawze Wrote:  

(10-18-2023 )Copper Wrote:  ... previous turbo went bad and started pissing oil into my intake manifold...

just some FYI:
almost always, turbo bleeding oil into the CAC is caused by excessive crank case pressure buildup. #1 cause = not changing the crank case filter often enough. Better yet, replace the crank case filter with a maintenance free one like shown here ...
ref: http://rawze.com/forums/showthread.php?t...50#pid8950

And yeah, you need to do a proper CAC/intake pressure tests to ensure your CAC does not leak down from 30-PSI to less than 20 PSI on one minute.

Also, if the exhaust is clogging up, it will starve the intake of air and cause turbo speed derates.

You need to also ensure that you are plugging the the IMAP sensor all the way into the herness connector firmly before putting it into the hole where it mounts. If your installing the sensor first, then trying to plug it in, it will often not plug in all the way.

Lastly.. don't rule out that the replacement turbo is not damaged. You might want to have the exhaust turbine blades checked (only way to check them fully is to remove the exhaust housing of the turbo) by a turbo shop to ensure the outer edges of the exhaust blades are not damaged.

If that EGR cooler is old, they are known for spitting random carbon chunks out, and damaging exhaust blades of turbo and making it have weak boost. I have seen people go thru 3 or 4 turbo's before figuring this out. It is a common issue with older trucks that are not deleted .. or even if they are deleted, and there is no block plate between manifold and egr cooler to prevent it.

The truck does have the maintenance free filter. Is there anything else that can cause high crank case pressure?

the truck seems to regen fine. Is it still possible the exhaust/aftertreatment is clogged somehow?

Thank you Mommaburt, Rawze, and Colter for responding.