Wanted to bump this to the top for any other information that people may have gleaned about low power/low fuel economy since I am suffering with this currently. I am curious about replacing the 02 sensors. I can't remember if we have one or two. Anyone replaced the 02 sensors and get fuel economy/power back?

Did you plug it into Xentry yet?

Any stored codes?

Ck. here:

http://www.peachparts.com/shopforum/diesel-discussion/372742-2005-6-later-e320-cdis-ck-clean-egr-valve.html

Gents,

I read thru this thread and I want to bring to your attention one more item that could trigger loss of power. In my case, 06 E320 CDI with 96kmi, I lost power when the swirl flaps link bar from the actuator fell off (detached). I consider this to be a difficult to find problem. There will be no code associated because the electrical actuator will still do its job, but because the linkage is not there the movement will not be transmited to the actual flaps.
Take a look and see if your linkage is still there. I attached few pictures to help you guys who are not familiar to find it.
I changed my link bar once and in a short time the link "cup" got worn off and fell again. This time I drilled a small hole thru the link "pin" and I secured the link assembly with a paper clip wire. I know that this time the link bar will stay there. ( see the pictures).

Great Post. Thank you.

I looked quick last night. On the CDI that I've been having "EGR" issues, that linkage is totally missing. On my other CDI, linkage is there.

My question. I haven't looked in ALLDATA yet, but how do you get access to repairing/replacing that linkage? It looks like it has to be all done from underneath.

Any update on this from OP? i have a 2007 E320 Bluetec (om642) that has EXACTLY the same symptoms.

Car behaves PERFECTLY in every aspect, except it feels underpowered.

-starts up quick without hesitation on even the coldest winter mornings.
-Checked every electrical sensor and actuator in DAS to make sure they were operating within spec.
-boost pressure and fuel pressure are within spec. fuel injector return rates are even and within spec.
-0 codes from anything, even scanning with DAS.
-Passes compression test in DAS

The transmission does shift strangely, almost like its shifting too harshly or not timed right, but it is very consistent.

I almost wonder if its a torque converter lockup problem.

Fuel Filter??
 

Has this come up at all in any post?

This was a killer for the OM60x series, insidious gutlessness, with no particular fault.

Thoughts?