Cleaning Intake Manifold
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Cleaning Intake Manifold What's the best way to clean the inside of an ls6 intake. I would just soak the whole thing in soapy water but there's a sensor on the back. The thing is filthy inside with oil. I don't know what's up with my engine right now. Took the intake manifold off when I first got the car about a year ago and the head intake ports were clean with a little bit of light goldish oil on them. I took it off again 6 months or so ago and the same. Now I seafoamed the car about a month ago (if it makes a difference) Now the intake ports are coated mostly black with burnt oil. Could the oil be coming from anywhere or is there a certain place that it could only be coming from? I'll be taking the heads off today or tomorrow to clean them and install new lifters.
When I had mine off the car I just sprayed the inside with carb cleaner and let it run out the front and the sides. If you wanted to totally sumberge the entire thing in soapy water, that sensor on the back just pops out.
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That's what I thought. Thanks, that will be what I'll do. I think I've got a fairly big mess here. Just checking out a few of the springs. A couple of the valve seals are up by the retainer. That just doesn't seem normal to me 
Yeah if u clean it on the car..GM makes top end cleaner and it works real well to blow all that crap out.. With it being off the car u deffinatley have a few more choices there.. Just make sure its dry when u put it back on.. The sensor should just unsnap thats on the back of the intake..
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When you say unsnap, is that just pull straight out or wiggle it or twist and then pull out... Also found two of the valve seals at the top near the retainer. That's definatly part of the problem right there. This is only on the passenger's side. I'll be putting in all new seals, cleaning the heads, and putting in new lifters. I have a feeling I'll be putting up quite a bit better numbers. Or at least I hope.
Yeah just play with it a little.. Maybe use a flat tip to gently pry it up..but it just snaps into place on the rear.. valve seals+oil hmm sounds like your onto something.. Its also a good time to clean up a little and do some inspecting while the intake is off.. I like to check out the ports to see if they are looking the same.. look at your plugs to is there was alot of oil in the intake area..
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Well to tell you something's up, my heads are ported but with stock valves and I made 386rwhp with the tsp231/237 cam. Definatly all kinds of crap in there. I'm cleaning them out right now and going to polish them up a little. The intake might get some engine degreaser or something. I just don't know what's best to clean it with. I know the degreaser worked wonders on the heads as far as cleaning off the burnt oil and what not.
