What a great site! It reminds me of the Ford-diesel website. Lots of good advice on both sites.
I am the second owner of this car. We got maintenance records with it. No problems until a month or so ago.
(Car has 85K miles) It began lighting the check engine light and setting codes. We cleared the codes and it reset code P1475. Some vacuum lines were replaced. It then set codes P0200 and P1475. The switch-over valve (002-540-06-97) was replaced. Now it has set code P1476, and the independent shop doing the work is telling me that the intake manifold is probably carboned up due to the combined function of the crankcase ventilation system and the EGR system both dumping into the intake manifold. Oil fumes mixing with hot exhaust gases and making carbon. Oddly enough, the original owner did have to have the manifold cleaned out once before. It seems that the carbon interferes with the operation of a set of air management valves in the tuned intake manifold. Thank you, EPA. I guess that I have a continuing problem if this is the case. If this is the problem and we get it straightened out, I am thinking of disableing either the crankcase vent system or the EGR setup to prevent the formation of carbon in the future. Is this problem common? Is there anither solution?
Do the codes I have described to you indicate this problem?
The car runs fine with or without the check engine light.
Power and mileage are great.
Thanks in advance if you can help me with this.
SBB.

About your '97 E300
 

Unfortunately, I cannot contribute to your posting, but I would like to converse with you about how you have liked your E300D. I have a '96 E300D with 69k still under warranty and would like to find out more about your ownership experiences.

I have had some bad experiences but I think that they are due to poor MB Technicians who were servicing the vehicle at the dealer.

Please let me know!
thanks
Richard

With OBD-2 on diesels the intake manifold flaps have been a constant problem. Surging & other problems on 1996 & early 1997. Check engine code P1 475 is related to the induction resonance flap. Cleaning the manifold & replacement of any sticking, binding, OR broken flap is the answer.
The P0 200 is generic & can mean 4-5 different items, including the P1 475. Might do search on OM 606 engine.
Some of the 1996 cars were a repair nightmare, SURGE!!!

I went through the surging problem from hell with my '96 E300D. It was one of the first of these to be shipped, and I suppose they hadn't figured out the problem yet. My car was their guinea pig. They ended up replacing ALL the valves for the resonance system. The problem went away. I'm sure they can home in on it much better now. With MB Doc's experience with this problem now, he could have probably replaced one part the first time and fixed it. Nothing like intelligence and experience with a particular system to make a good troubleshooter.

Have a great day,