Lot of grease/carbon buildup in upper intake

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Nov 4, 2010
Austin, TX
I am tearing into my FJ62 to make sure it is running the best it can and efficiently as well. I was removing the cold start injector and it was COMPLETELY caked with (what I think is) grease and carbon. I removedthe EGR as well and the entire tube was filled also. I removed the injectors to send off to witchhunter performance and the injector seats were caked as well. I got to looking at the upper and lower intake, I am concerned about this buildup. My question is what would cause this? if it is the head I will have a valve job and milled, I just do not know where to go from here. I do not have time to replace the rings but if that is it I would like to know. I am also wondering what is the best way to clean all of this out of the upper and lower intake. Thanks for the help, I am wanting to do all the cleaning tomorrow. Oh it has 213k on the odometer.

I am wanting to keep all the emissions in place, I am not wanting to desmog the 3FE. Thanks
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I am wanting to keep all the emissions in place, I guess I should have said that on my original post. So the EGR is the reason everything is all caked up?
It is a combination of the carbon from the EGR valve and oil from the PCV valve coating the inside of the manifold. The 80 series guys are using filters inline with the PCV valves to keep the oil from coating the manifold, no oil, no build up. Here's a link to the thread. A few guys are running oil separators for air compressors with good results.
Careful, you're going to stir up a hornet's nest! If you do decide to start this project, at a minimum, you're probably going to want to clean both the upper and lower intakes as well as the head. For cleaning purposes, try using the heavy-duty, spray-on oven cleaner from your local grocery store for the aluminum intakes. Let it sit for 15 mins, and then take it to a car wash and blow the gunk out of there with a pressure washer. You'll need to do this a couple of times before you get all the build-up completely out of there. Ultimately, it will take a little work with a stiff nylon brush to clean the runners as well. As far as the head goes, you'll have to remove it and take it down to the machine shop and get it soaked/cleaned up. (Might as well get a valve job while you are there.)

Unfortunately, as with most "small" projects, it can get quite involved...

Here are some pictures of what mine looked like before I cleaned it: (I had build-up in excess of 1/8" at the top of my intake manifold)

Intake Manifold.jpg

Intake ports on head..jpg
Intake ports on head..jpg
Intake Manifold.jpg

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