Manifold caked with filth

I am unfamiliar with snorkels. Does the snorkel have its own air filter? Or does it pass through the normal one? Or is there both?

 

the snorkel passes through the OEM airbox.

 

yes

 

should I do this as part of my overall maintenance efforts with this issue?

 

do you know if this screen can be replaced? it looks like it is permanently attached.

 

I run a dry filter that is rated at 99.4%. Injen’s intake is the best.

 

Are you 100% sure that the intake manifold can't be flushed out without causing harm?

 

I don't think so. you'd have to replace the whole upper box lid portion. check around the for sale sections.

 

It is not available by its self. You will have to source a complete lid

 

Could this be EGR gunk?

 

Just keeps getting better. Lower manifold removed...

 

Valve stems look good. Set 1st cylinder to TDC, clean that cylinder intake ports, vacuum the top of the valves, set next cylinder to TDC and repeat. This way the crap won't enter the cylinders

 

My pictures are out of focus but you are right. the valve stems do not seem filthy.
I've been researching how to close the valves. No luck finding a solid source yet. I guess this is what you are referring to "TDC".

 

looks really oily - is it? i really wonder if you’ve got EGR gone wild.


what’s your filter look like?

 

Piston at Top dead center. Valves are closed so the dirt won't get inside when start
cleaning. May as well stuff a rag in there.

 

You can try but atleast in gm land, if you have a major engine failure then it's standard practise to replace the manifolds because due to the time and passages of the manifold a proper cleaning can't be guaranteed it's part of the engine replacement that the manifold be replaced and exhaust cleaned well so that as the engine cranks/runs it doesn't suck a particle in that was missed and cause future issues.

To close the valves you just spin the engine over (clockwise) via the crank pulley or if you're, lucky by the alternator pulley until you see both valves firmly closed as the piston is on it's way up. Or if you wanna be more scientific then once you figure out one cylinder's tdc then rotate the crankshaft pulley 120* (for a 6 cylinder engine) and look for the next cylinder with it's valves closed and do that one next

 

The crankshaft pulley has marking (0°).
You took spark plugs out. I think you need 17 or 19 mm socket and start rotating the crankshaft clockwise until the mark on the pulley lines up with 0° mark -this is cylinder 1 tdc. Or stick a long rod inside of the spark plug hole and rotate crankshaft until the rod stops go up and is about to go down

 

I may be wrong but I don't think these engines have EGR. It appears egr is achieved by programming of the vvt

 

it does look oily, but I have not yet really begun cleaning yet to get a good look. My filter is fine, I believe this build-up occurred quite some time ago.

 

Also note that it wouldn't be spot less in there. All engines consume a little oil through the intake. The debris is the main issue