Welcome to the addiction.
The only sure way to clean out an intake is to remove it and wash it out by soaking and scrubbing it with diesel fuel or a chemical cleaner.
This would involve removing the valve/cam cover assembly which means removing the timing belt and the cam pulleys.
You did not say how many miles was on it, but while you got it apart it would be time to replace the cam belt, cam belt idler pulleys, water pump (turned by timing belt) and cam belt tensioner.
Also while it is off, replace Glow Plugs if they have not been replaced (very easy to get at with intake off) and inspect rockers for wear and replace them if needed as they will be staring you in the face.
Another recommendation is to replace head bolts with ARP head studs.
You also need to disable the EGR system to stop the flow of soot into the intake where it mixes with oil from the CCV system to make the carbon sludge you feel and what is pictured below.
Blocking off the EGR or totally removing it along with installing a ProVent filter will stop this. Covered in other posts on this forum.
The CAC (intercooler) is probably has a good bit of oil in it which can cause the sudden engine accelerations so it needs to be pulled and cleaned out.
This engine requires a good bit of maintenance and money to get it into a reliable condition.
I may have missed a few, but I am sure others will offer suggestions....lots of good help and information on this forum.
If you have not read the NOOB guide, you need to do so.
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Supporting Vendor and Moderator of LOST05 Jeep Liberty CRD Limited
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