Carbon Build-up in EGR and Intake Manifold
11-03-2005, 01:04 PM
#81
Originally Posted by 1MAX2NV
looking into the intake manifold. See the hole? That's where most of the build up will be.
http://www.picturelist.com/images/1max2nv/Dcp00808.jpg
This is a shot where the EGR valve goes.
http://www.picturelist.com/images/1max2nv/Dcp00807.jpg
http://www.picturelist.com/images/1max2nv/Dcp00808.jpg
This is a shot where the EGR valve goes.
http://www.picturelist.com/images/1max2nv/Dcp00807.jpg
Does anyone have any other pictures, I just realized how old this post is.
11-03-2005, 01:17 PM
#82
Originally Posted by vpmax2
Actually this makes alot of sense. What do you consider a long long time driving around with this condition... Several weeks or several months?
I noticed the right angle bend and obviously the larger particles will be confronted with some kind of resistance. Enough of these kind of components flowing through there will eventually stack up on each other and start to clog the line.
Is this side of the small pipe difficult to remove the bolts? If just the intake manifold is removed, the small pipe will just stay there open. Did you see the clogging in the pipe and if so how did you clean that? I don't want to attempt to open the EGR part of the system again as I had minimal luck doing so.
How difficult was it to remove the manifold and that side of the tube? Did you replace the gasket on the manifold also?
I noticed the right angle bend and obviously the larger particles will be confronted with some kind of resistance. Enough of these kind of components flowing through there will eventually stack up on each other and start to clog the line.
Is this side of the small pipe difficult to remove the bolts? If just the intake manifold is removed, the small pipe will just stay there open. Did you see the clogging in the pipe and if so how did you clean that? I don't want to attempt to open the EGR part of the system again as I had minimal luck doing so.
How difficult was it to remove the manifold and that side of the tube? Did you replace the gasket on the manifold also?
After 10 yrs and 125k, here is what my EGR port on the plenum and guide tube looked like:
Removing the plenum is one of the more involved jobs. It's not magic, but I'd rate it a 6 on a scale of 1 to 10. There is a lot of stuff that you have to undo/move before even getting to the plenum. Once you have all the other crap out of the way, the plenum itself has 4 bolts up front and 2 behind - that are a little harder to reach (you can't really see them, so you have to work by feel only). There are a bunch of coolant lines, vacuum lines, etc. that you have to disconnect, in addition to the throttle cables, main harness, removing coils, a purge valve... all that crap has to be unbolted from the plenum and moved out of the way.
The EGR guide tube bolts that connect the tube to the plenum weren't hard at all (for me), and I live in the snow-belt...
I would suggest removing the throttle body and IACV.. that will give you much better access to the EGR tube bolts and the rear plenum bracket bolts.
Once you have the stuff dismantled, I just used a pick a lot of carb cleaner on the plenum port and used just a pick to clean out the guide tube. I didn't want to spray a bunch of carb cleaner down the tube into the valve (perhaps it would be ok, but I didn't want to chance it).
I replaced all gaskets - gaskets are cheap and I didn't want to skimp out for 20 bucks worth of gaskets and then end up having to disassemble everything again to fix a pesky leak. (EGR-> plenum gasket, IACV gasket, TB gasket, plenum gasket).
This would be a good time to make sure your rear valve cover isn't seeping/leaking oil and the spark plug tube seals are still intact. Once you have the plenum off, its easy to pull the valve cover and replace any assocated gaskets/seals while you are at it. I did (I actually had two problems to fix, the EGR clogging and a bad spark plug seal).
I went through this twice over the summer, so most of it is fresh in my mind.. feel free to ask me any questions you have.
Long-reach needle-nose (straight and 45 degree bent) pliers are a must for this job.
11-03-2005, 06:57 PM
#84
I've taken the upper plenum off before and cleaned it out and let me tell you, there was a lot of crap in there, it was worth it. The most important thing is to label as many hoses as you can with painters tape or something. It took me 3-4 hours to take apart and clean and 2 hours to get it all back together. This can be done on your own. I would recomend using locktite on the throttle body and iacv bolts when putting everthing back together.
11-03-2005, 07:05 PM
#85
Originally Posted by crazy97
I would recomend using locktite on the throttle body and iacv bolts when putting everthing back together.
11-03-2005, 07:37 PM
#86
Originally Posted by njmodi
Why? I disagree. They didn't have any thread locker on them from the factory, and there is no reason to add any - but I'm open to being convinced otherwise.
11-03-2005, 07:40 PM
#87
Originally Posted by crazy97
I had the iacv bolts come loose and I even lost one. I'm pretty sure they were tight but I could have missed tightening it down, but I doubt that is the case. As for the tb, they are the same type of bolts so I put loctite on them too.
11-03-2005, 07:51 PM
#88
Originally Posted by njmodi
Hmm.. interesting... I have NEVER heard of that happening to anyone yet... but I guess there is always the first time... As you said, perhaps you didn't tighten it down. I guess using the loctite that holds bolts tight (as opposed to the type the locks them - red vs blue).
11-04-2005, 01:53 PM
#90
Originally Posted by edwardh1
can you just take off the throttle body and stick like a coat hanger (bent at end0 into the intake and push out the carbon from the hole??
enough hand-holding... read the stickies, get a haynes and get to work. 
Throttle cable removal is the trickiest part. 
01-16-2011, 08:20 PM
#100
Junior Member
Join Date: Nov 2010
Location: Mount Prospect, IL
Posts: 48
The search function might be your best option at this point. From personal experience I can say that when cleaning the throttle body that you don't need a coat hanger to scrap out carbon. Just take off the IACV and scrape what you can get out with a toothbrush and some carburetor cleaner through that opening. After that get a flathead screwdriver (more durable than a coat hanger) scrape out all the carbon and then use the toothbrush again.
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