'94 850 Turbo - Excessive buildup in intake?

[IG-88A]

'm a couple of years into Volvo ownership and recently acquired my first turbo. Smoked from exhaust and dipstick tube upon purchase, so I assumed that I'd immediately replace the pcv system and clean the ptc as well. So I was tackling the pcv job today and discovered a ton of extra gunk in the intake ports as well as the manifold itself. The throttle body was pretty caked as well. I didn't notice things looking quite this gruesome when I serviced the pcv on the naturally aspirated wagon. Should I be concerned? Or will a seafoam treatment or several clear this up after reassembly? I noticed some "chunks" had come free upon removal of the manifold and tumbled downward. Should I try extracting them somehow? Or will they simply burn away? Or should I just be pulling the head at this point and have it redone?

[kahl]

we recently did our PCV on the 95 850 N/A. Our intake was very similar. I am looking to do a cleaning with chemicals called terra clean. basically two different chemical are pumped through the intake and allegedly removes carbon on the valves and intake. From what I have researched this process has been around for several years.
While doing the PCV I used a rag with sea foam cleaning the intake as best I could get. I also cleaned the throttle body and the EGR. There are many posting and vids using sea foam injection while the car is running.

[tryingbe]

Clean it while the intake manifold is off!

I used carb cleaner to clean mine. Just make sure all the valves are closed and do 1 cylinder at at time. I used rags, carb cleaner, and compressed air.

[rspi]

If the car runs fine, leave it alone. I wouldn't even do a seafoam treatment. I have seen plenty of filthy intakes. It would be impossible to get all that stuff out of there. As long as the valve seats are clean and sealing the car will run good.

I run Lucas injector cleaner in mine every 2,500 miles which is suppose to clean valves as well.

My concern is that you can knock some of that stuff loose and a chunk of it get caught in a valve seat and chip a valve.

[kcodyjr]

Following up in case someone comes across this thread.

That's not carbon in the picture. Carbon builds up on the interior surfaces of the cylinder, and along the exhaust valve path, from partially burnt fuel and burnt oil.

What you're looking at is oil that landed there and got literally pan-fried by the hot metal. Much lower temperatures than post-combustion. It shouldn't be as prone to chunking. It's the same stuff you get when you re-season a cast iron frying pan, just made with toxic petroleum oil instead of canola oil.

Seafoam might or might not even touch it, and anyway the seafoam would only pass through the ports themselves, and in atomized form (read: air-diluted), not the throttle body and manifold.

I'd spray the heck out of it with carburetor cleaner, but I wouldn't risk trying to mechanically clean the intake ports with the head attached. I would take off the throttle body and clean that, and the plenum, with a rag and carb cleaner.

There are two potential sources for the oil. One is normal, the other is not. Oil vapors are normally sucked through the intake from the PCV system, where they cool in the fast fresh airflow and condense on the inside of the pipes. That's what the PTC nipple is for; to pre-heat the oil vapors so they don't condense quite so readily.

The other possibility is an internal leak in the turbo. There should be copious amounts of fresh oil in there if that's the case.