Soot in intake manifold

[MitsGSX]

I just pulled off my throttle body to replace a gasket and when I looked in the manifold the entire inside was lined with a layer of black grimy soot. Is this normal or should I be worried?

 

[Low Impedance]

sounds like the oil bypassed from the PVC valve.

 

[dsmdragon]

Well, if it was normal then you wouldn't be asking about it. Also All you should do is just take it off get some brake cleaner and spray the inside of it. I will help with a lot of things if you do. Also don't forget to take the sensors off the manifold and don't forget to let it dry first.
The black stuff you are so worried about could be a number of things like oil going through your system or blow back of exhuast in to it. also like just grim from not being clean in forever.

It's not going to kill your motor, but it will lose you some HP and maybe some mpg

 

[DSMunknown]

That's normal. Don't worry too much about it (unless you are planning to take it off for some reason). I just bought a used intake manifold and it was lined with that black crap.

 

[red_devil]

Its called carbon build up and happens in every car so its not a big problem.

some ways to fix it
-Spray intake cleaner or brake cleaner in there-let it set for a while then run the car it will run bad for a while but get better.
-Take the pcv hose off and spray some cleaner in there. (can be done while running).
-Auto tranny fluid will also clean up the intake....lots of smoke.
-Combustion cleaner or mopar intake foam works well.
Local lube shops have a fuel syestem service which they use a high power spray to clean the intake out.

Try a mixture of things. You may need to take the spark plugs out after and clean them of.

 

[blazebolt]

Running seafoam through your car will clean that up (there's a huge thread out there on seafoam), but since you have the throttle body off, just clean it with brake cleaner as red_devil suggested.

 

[flyinghighlm]

Block off your EGR valve as well, it will prevent alot of that carbon from building up