I have decided to inspect all the fuel line o-rings, all of them.
I have also decided to clean the carbon soot from the intake manifold, assembley. That will be a chore.
As an update, we have seen this complaint on 1995, 124 chassis 606 engines and 210 chassis with 606 engine and replaced both Y31/1, (EGR Transducer) & Y31/2 (Pressure control flap transducer) with success. We replaced them early on with this auto with no results. All vac lines have been inspected, vac applications tested and all found to work. In theroy, the Y22/6 (Resonance Manifold switchover valve) & Y22/7 (Resonance Line switchover valve) should through a code if malfunctions. I have unpluged and run for grins and found 'Check Eng" light comes on. But with above suggestions, I have nothing to loose by replacing them. Again, the EGR is electrically monitered and should code, but a good cleaning is still a good idea. I will try the suggestions above and let you know how it comes out.
* I would like to pass something on I have found. We are lucky to have a nice customer and time hasn't been an issue yet. I have viewed the operation of the 124 chassis 606 on other cars that come in and also viewed the operation of the 210 chassis 606, non turbo's.
Resonance Intake Manifold: From CTP to 2550 rpms, both 99/2 (Intake Line Flap-middle of long intake pipe on top) & 99/4 (Intake manifold flap) are closed. From 2550 rpm to 3350 rpm, 99/2 opens & 99/4 stays closed. 3350 & up both are open.
* In viewing a 124 chassis 606 engine, the above was true.
* In viewing the 210 chassis 606 engine that I am working on, I found the opposite happening from 2550 to 3350. 99/4 would open and 99/2 would stay closed. All electrical connections seemed factory. I swapped the vac lines at the swithover valves, Y22/6 & Y22/7, to generate the operation the book calls for and the car runs much better and more pep.
You might know the Mercedes HHT showed 99/2 opening when it really was 99/4 opening before the swap.
* Here's the kicker, another 210 Chassis 606 rolled in for an oil service and it was doing the same thing. I don't know if I have found a true MB foul up or not.
Could this community with the 210 Chassis 606 engine look to see how there resonance flaps are working? This is very hard to put into print and know if I have described what I have found in an understandable way or confused everyone.
Thanks, Michael

I have a 97 E300 W210 with the 606 engine.
It seems MB design of the Resonance Flaps in the intake have many problems. I guess they dont do recalls for bad parts. My car has 70k miles and is pristine. Not much soot to speak of.
Can someone give me detailed explaination of how these expensive (2) transducers work?? I would also like to know how to check them, Ie resistance checks or electrical checks? I dont want to willie nilly change them. I swapped them around and it seems to have worked.
The problem I notice is - if I put it on cruise control at 55mph or just hold my foot steady at this speed - the car goes into surging mode- rpms also track the feeling. At idle is this flapper suppose to gyrate all the time?

Can someone point me to a link to help me isolate which of these is bad- I would hope they both are not bad.

Bill

It is better to start your own thread and to describe ALL you problems at one time in one place than to tag onto old threads.

You'll get better help that way.

The first thing to do is ALWAYS fix the fuel leaks first (see your other thread). They can be the "cause" of other issues.

After that, if other symptoms remain, THEY can be dealt with in a logical progression.

Very often a good cleaning of all the gunk that collects in the egr and resonance flaps helps surging/lack of power issues.

__________________
Terry Allison
N. Calif. & Boca Chica, Panama

09' E320 Bluetec 77k (USA)
09' Hyundai Santa Fe Diesel 48k (S.A.)