EGR Transmission black cam with lotsa hoses thingy - PeachParts Mercedes-Benz Forum

zu! · #1 11-23-2010, 12:46 PM

Well, it was clear down to -6 in Richmond BC yesterday and it was my daughter's birthday so I wanted to get home early. Left work at 2.30 and realised I had forgotten to plug the car in (I like heat eh). No worries, car started up within a couple of cranks, but was idling rough due to the cold. I gave it some fuel via the pedal for about 30 seconds then let off. That's when things got interesting.

The pedal became hard to step on. And the car would not go above idle. Damn. Just when I needed to go home early. Got out and popped the hood and realised that shorts in -6 is no fun. Well, it was quite fun under the hood. Pressing down hard on the IP linkage brought the engine slightly above idle. But that was it. All linkages appeared good, and all hoses appeared to be still connected. Oh well. I got CAA, might as well use it (never used since I got it!!). Got it towed to my mechanic.

He looked at it real hard, tested the linkages, then stuck his screwdriver someplace and asked me to try revving the engine. Lo and behold, it worked!! Well, his simple fix was this:

Cut off a small piece of plastic from the bottom of an RTV tube.
Jam said plastic sliver into the cam thingy on top of the valve cover.
Glue said piece using the same RTV that the piece was cut off from.

Voila! Car runs like a top!

Here're a couple of pictures:
This one here shows the glued on piece. See that top metal pin that rides on that flipper thingy? In the bottom one, the flipper must've broken when I stabbed the pedal to give the engine some fuel. Probably frozen right off and being a 26-year old plastic part, probably said, enough was enough and broke on my daughter's birthday.

The view from the other side. What the heck do these things do anyhow? BTW, the reason its all grimy is because it never had the black cover that I see on other cars. Its always been exposed like this.

Here's what it looks like from farther away.

Now I've read on this post about the EGR blocking and stuff. The thing is, how will this actually affect emissions? Does it help reduce emmisions? Increase it? I also saw a pix of an EGR on a VW that was literally full of crud. Can't be too good for the car now. I also read about using a BB to block off some hose? How does that work?

We have tailpipe testing here in BC and it basically measures the amount of soot at the tailpipe. Basically an opacity test. My merc has never failed before. Will removing all this fail it?I know that plastic flipper thing is probably cheap, but if its just another unnecessary part, I'd much rather do without it if I can.

Let me know what you guys think, thanks!

toomany MBZ · #2 11-23-2010, 02:02 PM

That is part of the emission system and you have tests, right?

So I'll suggest if anything to have it like the way it is when go to have a test performed, otherwise it can be removed (unplugged) and yes, it tells the intake to have exhaust introduced into the manifold, burning hot dirty exhaust fumes, not good.

Seems I have a different line routing. The one in the pic came of of my SD, note the broken levers and cracked plastic surround at the screw. It's seen better days. I have bypassed the egr system, we don't have smog tests here.

The last pic is from the epc, that may help too.

BoiseBenz · #3 11-23-2010, 04:20 PM

The little flippers are replaceable, as are the valves in their entirety.

One valve controls the idle signal, one the WOT signal; EGR operates between those extremes to reduce oxides of nitrogen (NOx). It has no effect on opacity (soot). Take the cover off, take the valves off, stash the valves in a box, and reinstall the cover. Plug the line from the cover down to its vacuum source. No more valve troubles.

PS Move someplace warmer???

Who am I kidding, cold spell here -4 dF / -20 dC tonight!!!

zu! · #4 11-23-2010, 05:54 PM

Thanks for the replies guys. I'm now in two minds as to whether I should do this or not. I would surely like to have it completely unplugged, if it helps simplify the whole vacuum thing. I suppose once unplugged, the entire Cam and hose assembly becomes redundant? So I can actually remove the whole assembly without fear of the car going kaboom? Does the EGR actually help reduce emissions or was it just a stopgap measure that Mercedes added on to get the car into the market?

Its not really cold here. Just -12 predicted and the usual "windchill" nonsense. I don't believe them. I'm still in shorts.

toomany MBZ · #5 11-23-2010, 08:00 PM

No problem, see pic, been like that for years.

What the SD looks like now.

zu! · #6 11-24-2010, 10:56 AM

Quote:

Originally Posted by toomany MBZ

No problem, see pic, been like that for years.

What the SD looks like now.

Cool! Looks like you didn't even bother with removing the EGR as well and just plugged the hose? What do you do with all the other hoses that go out of/into the various places? Just plug them?

andrewjtx · #7 11-24-2010, 11:16 AM

Rip 'em out.

toomany MBZ · #8 11-24-2010, 12:18 PM

Quote:

Originally Posted by zu!

Cool! Looks like you didn't even bother with removing the EGR as well and just plugged the hose? What do you do with all the other hoses that go out of/into the various places? Just plug them?

Correct, maybe one day I'll remove the valve.

As far as the other lines, the end connectors were replaced with a one fewer connector. One (top of the VCV) was a four way, now a three way and the other was a three way (bottom side of the VCV), now just a piece of hose to the vent.

Evil Monkey · #9 11-24-2010, 09:15 PM

Removing the valves is an illegal modification to the emissions system.

Mark DiSilvestro · #10 11-25-2010, 09:03 AM

And some of the W123 diesels also use this valve device to regulate the vacuum signal to the automatic tranny vacuum modulator.

Happy Motoring, Mark

whunter · #11 11-25-2010, 03:04 PM

Quote:

Originally Posted by zu!

Well, it was clear down to -6 in Richmond BC yesterday and it was my daughter's birthday so I wanted to get home early. Left work at 2.30 and realized I had forgotten to plug the car in (I like heat eh). No worries, car started up within a couple of cranks, but was idling rough due to the cold. I gave it some fuel via the pedal for about 30 seconds then let off. That's when things got interesting.

The pedal became hard to step on. And the car would not go above idle. Damn. Just when I needed to go home early. Got out and popped the hood and realized that shorts in -6 is no fun. Well, it was quite fun under the hood. Pressing down hard on the IP linkage brought the engine slightly above idle. But that was it. All linkages appeared good, and all hoses appeared to be still connected. Oh well. I got CAA, might as well use it (never used since I got it!!). Got it towed to my mechanic.

He looked at it real hard, tested the linkages, then stuck his screwdriver someplace and asked me to try revving the engine. Lo and behold, it worked!! Well, his simple fix was this:

Cut off a small piece of plastic from the bottom of an RTV tube.
Jam said plastic sliver into the cam thingy on top of the valve cover.
Glue said piece using the same RTV that the piece was cut off from.

Voilà! Car runs like a top!

Here're a couple of pictures:
This one here shows the glued on piece. See that top metal pin that rides on that flipper thingy? In the bottom one, the flipper must've broken when I stabbed the pedal to give the engine some fuel. Probably frozen right off and being a 26-year old plastic part, probably said, enough was enough and broke on my daughter's birthday.

The view from the other side. What the heck do these things do anyhow? BTW, the reason its all grimy is because it never had the black cover that I see on other cars. Its always been exposed like this.

Here's what it looks like from farther away.

Now I've read on this post about the EGR blocking and stuff. The thing is, how will this actually affect emissions? Does it help reduce emissions? Increase it? I also saw a pix of an EGR on a VW that was literally full of crud. Can't be too good for the car now. I also read about using a BB to block off some hose? How does that work?

We have tailpipe testing here in BC and it basically measures the amount of soot at the tailpipe. Basically an opacity test. My merc has never failed before. Will removing all this fail it?I know that plastic flipper thing is probably cheap, but if its just another unnecessary part, I'd much rather do without it if I can.

Let me know what you guys think, thanks!

Here is the part you need.

Fastlane: Vacuum Valve Lever 3/2 Way
http://catalog.peachparts.com/item.wws?sku=W0133-1640593

IMO: Don't remove it, slip a BB into the EGR vacuum hose and re-connect it.
It will have Zero impact on your opacity test.

Nothing negative/bad will happen..

.

Alastair · #12 11-25-2010, 03:27 PM

IME, to dis-able the EGR will have a beneficial effect on the smoke-readings during emissions testing....

hey_allen · #13 11-26-2010, 07:07 PM

From what I was able to figure out in reading the related manuals, and digging around in the plumbing, the two vacuum valves on the valve cover also control the vacuum signal to the transmission, so it's not a great idea to remove them unless you really like the automatic transmission shifting hard all the time.

When I got done replacing the engine and transmission in my SD, it was shifting hard until I traced down the vacuum leak to the five connection plug that connects to this vacuum switch assembly. Once I removed the cast rubber plug that had hardened and used a few pieces of hose to connect the plastic tubes, the shift became much smoother (though not nearly as smooth as the actual manifold vacuum regulated shifts in my SEC.)
As WHunter mentioned, the replacement levers are available, and fairly easy to replace as well. They wear down over time, as the upper one in the picture shows.

Kudos on the ingenuity to get it home, regardless!