Hey Guy, i may be asking a dumb question here but im sure someone will be kind enough to help out. I took off my upper plenum today to replace a faulty gasket, after removing i notice apot of build up in the plenum and was wondering if it was normal, and what can i use to clean.

 

It is normal. I've cleaned mine with mineral spirits. It's just oil that is picked up from the PCV recirculation line to goes back to the intake tube.

 

I used engine degreaser

 

nothing to worry about and I just used parts/brake cleaner when I had mine apart-super easy+fast.

 

Thanks!

 

Throw on a catch can if you don't want so much buildup. After swapping out my plenum for a ported & polished one and noticing the buildup, I installed one on my passenger pcv valve.