lots of greasy oil at intake manifold - PeachParts Mercedes-Benz Forum

clint77002 · #1 03-31-2006, 12:01 AM

While looking for oil leaks, I noticed some coming from the bottom of the intake manifold. After pulling the air filter I was amazed at the amount of oily grease on the intake manifold. Inside the manifold was a lot of carbon build up. I bought the car almost 2 years ago and had it looked over by a mechanic that I trust and respect. He told me the engine and tranny were good and strong. Neither has given me any real problems but after seeing this I'm concerned. The pics of the manifold are attached. Here are my questions:
Is this amount of build up and oil normal? ( I doubt it. )
What could be the cause? (Possibly intake valves way too tight and not closing properly?)
Will a valve adjustment remedy the problem?
Can I/should I pull the manifold and clean it?

Oh, mileage is around 160K (odo stopped at 120K before I bought it).

SD Blue · #2 03-31-2006, 12:10 AM

Is your EGR valve still operational? If you do a search for intake manifold and crud build up you will be amazed at how bad it can get. Some folks have had a BB accidently get lodged in the vacuum line attached to the EGR.

ConnClark · #3 03-31-2006, 11:02 AM

Crud from the EGR is common in these cars. As far as pulling the manifold and cleaning it the crud isn't doing your engine any good, but on the other hand yours doesn't look too bad. Its your call, clean it now or wait till it gets worse.

sailor15015 · #4 03-31-2006, 11:16 AM

I'd clean it since the manifolds aren't that hard to get off then plug the egr so it doesn't happen again. That way you can have peace of mind. That's what I plan on doing, at least.

hawthorne90250 · #5 03-31-2006, 06:24 PM

I Doubt if plugging the EGR will do much good, i do not have a EGR on my car and my manifold is full of crud from the PCV system, i am thinking of cleaning it and installing a catch can from Summit Racing.

Brian Carlton · #6 03-31-2006, 06:34 PM

That manifold is quite normal for a vehicle with 165K. The SD looked just as bad (180K).

If you pull the manifold, you can spend about three hours with a brush and mineral spirits to dissolve all that crap.

As mentioned, disconnect the EGR in the attempt to reduce this buildup in the future.

djdluck · #7 03-31-2006, 09:57 PM

In my 2000 jetta TDI, to prevent this same thing from happening, I....

1. Disabled the EGR system
2. Disconected the crank case vent from the intake and ran an "elephant hose" from the CCV to the ground...

I havent heard #2 mentioned here yet, but would it cause any problems?

thanks!

SD Blue · #8 03-31-2006, 10:59 PM

#2 not really a good idea.

Dirt Collector for the oil system with direct access.
Port for mud daubers.
Oiling of the underside of the car. Oil degrades rubber suspension components.
On a 2000, why would you have that much blow by?
Pollution.

clint77002 · #9 04-01-2006, 12:16 AM

Thanks for the info. I do believe its the EGR and I'm not so worried anymore. I'll "fix" the vacuum problem w/ my EGR. I'd hate for one of my son's BB's to fall into the vacuum line but, those things happen.

I'll put the cleaning on my list of things to do...right after repairing all the vacuum actuators for the A/C...Texas summer is upon us and the stop and go traffic in Dallas doesn't lend itself to the old 4-60 air conditioning.
Thanks again,
Clint

#10 04-01-2006, 01:45 AM

"Dirt Collector for the oil system with direct access." The tube is much too long for water and dirt to get into the crankcase.
"Port for mud daubers." The tube will have a coat of oil in it. Not very welcoming to anything.
"Oiling of the underside of the car. Oil degrades rubber suspension components." True. But I'd bet the oil from the engine makes more of a mess.
"On a 2000, why would you have that much blow by?" All engines have blowby. No filtering system in the world can get all the oil out of the crankcase air.
"Pollution." BFD. Running without an EGR will put out far more NOx than the tube would release in HC's.

BTW, 99.8% of all medium/heavy duty diesel trucks have a road draft tube and don't re-use the blowby gasses.

I've run with a road draft tube for more than a year now without any problems.

andmoon · #11 04-01-2006, 03:59 AM

catch can?

SD Blue · #12 04-02-2006, 06:05 PM

Quote:

Originally Posted by ForcedInduction

The tube is much too long for water and dirt to get into the crankcase.
How could it be too long for dirt to get in there.
The tube will have a coat of oil in it. Not very welcoming to anything.
Since when did this stop mud daubers?
True. But I'd bet the oil from the engine makes more of a mess.
On a 6 yr. old car? Why just keep adding to it?
All engines have blowby. No filtering system in the world can get all the oil out of the crankcase air.
Why do a completely unnecessary modification?
"Pollution." BFD. Running without an EGR will put out far more NOx than the tube would release in HC's.
Who said anything about NOx? Pollution, as far as I'm concerned, is not some B.S. about greenhouse gasses purported by bad science but about not dumping filth onto the roadways, etc..

BTW, 99.8% of all medium/heavy duty diesel trucks have a road draft tube and don't re-use the blowby gasses.
Are you stating that they do not use any way of separating and returning the oil? Better double check that.

I've run with a road draft tube for more than a year now without any problems.

I just said it wasn't a good idea due to the items I mentioned. Sure you personally may have no problems with dumping filth but I do. Therefore don't take it personal when I point out other factors.

Diesel Giant · #13 04-02-2006, 06:26 PM

That amount of buildup is not very bad at all given the mileage. Just remove it and clean it out. You will have little or no noticible engine running improvement.