EKAS end position measurment

silverstar84 said:

2007, 906.635/642.993
Code: 2952-001,
B90/2 (Left EKAS end position measurement sensor)
The valve is closed. Readout too large

Inlet port shutoff positioner-M72 connects the Left and Right EKAS rods.
In trying to determine why, during actuations, my left EKAS sensor reads OK one way, NOT OK the other.
I have found the linkage from the M72 to the left intake lever or swirl flap guide,
is connected with a bright metal 2 piece linkage which appears to be spring loaded.
This is only on the left side, the right does not.
I’m thinking this is an adjustment I found it to be loose.
However I don’t know if it is loose for the spring tension or is it supposes to be tight.
I’m hoping it should be tight and maybe this is the reason for my bad reading on the EKAS sensor.
Unless I had a motor apart there does not seem to be anyway to provide pictures of this beast.
Can someone shine some light for me?
Please.
Michael

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silverstar84 said:

Yes I have SDS.
My goal this AM is to see if I can activate the M72 while I have at least 6 different electrical connectors disconnected required to move all the stuff out of the way so I can see the effects of the test.
It would make since the spring loaded clip would be an adjustment. Thus it should be tight.
The spring loaded part throws me because it could be argued to be a buffer of some sort.
I plan or hope to talk myself out of that.
I will keep you posted.

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lindenengineering said:

Well glad you like the comment.
Seriously though its carbon that is the killer on these engines and heat generated by regeneration.
I have a 3500 Sprinter box truck I have just sold to a moving company.
Exhibiting this EKAS measuring fault it got progressively worse as we used it for parts runs etc.

So it was due a teardown removing the manifolds and cooler. (for a re-seal)
Yes and Yes upon teardown the driver's side link was worn especially at the back which obviously denotes heat attack judging buy the edges of the pivot having melted!

Now sometimes you can clear this fault if it's not linkage related worn by doing a BG upper cylinder purge . Then sometimes it is unsuccessful.

So setting out to maybe get some answers we did the purge out prior to teardown.
Results were shall we say interesting!

The EGR cooler was cleaned fairly well but was patchy in places--how much it was plugged up before we had a go at it is anyone's guess! Inconclusive this !

The EGR valve was cleaned very well! Wow nice job!

So was the transfer port tube and the inlet distribution horn. Yes cleaned !

The unit must have had some sort of leak at the O ring where the horn meets the inlet manifold of the passenger's side manifold because we left the rig "as is" post test for about a month before tear down.

The carbon dwelling in that inlet tract turned to a thin liquid like tarry fluid before dripping out through the defective O ring seal filling the engine valley with a carbon liquid morass.
Upon removal the inlet horn was almost cleared out with a few thin patches of carbon in place. Very good!
The passenger's side inlet manifold and porting was cleaned, a few patches and stains but cleaned.
Now the drivers side--wasn't cleaned--OK the carbon was like a paste in the manifold and ports and though heavily carbon coated it could be scraped off--but wasn't cleaned as expected !
The air flow might have caused some stripping in subsequent service but wasn't as conclusive as hoped!

I took the observations up with BG but as yet they don't or won't comment !
The manifolds are saved for examination being worn beyond further use!

Now part of this purge out is to run the engine on a carbon stripper in the engine oil for 30 minutes at a high idle for 1500r/m.
Having put fresh Rotella T6 in it (for test purposes plus a new filter) the test was conducted as prescribed but we left the engine "as is" for about a month without running it!
Now this BG purge additive is high in phosphorus which strips out carbon!

AND strip it out-- it did!
Dropping the oil was a sludge of liquid carbon and what is lying on the sump floor like the rig has never had an oil change in its 250,000 mile recorded life!
Its going of for test analysis.
The oil filter was choked! How much by who knows -its needs a test!
Remember this rig had a regular service schedules done to it by Fed Ex the previous owners and was disposed of!

So it will come as no surprise that carbon is the killer of this engine and why it will go tits up at 250,000 miles if you don't take care of it!
Dennis

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lindenengineering said:

Well of course you on the wrong side of 2010 onwards year Sprinters .
Those EKAS systems on previous engine (CD14 versions) were prone to early failure due to wear in the linkage, and attack from reflected turbo heat especially on the left side of the manifold set .
Its fairly obvious that MB with Pierborg the manufactures, took steps to improve durability which was pretty dismal , but a good shop revenue earner nonetheless,, we used to do about 2 per week.
Frankly if the EKAS set has done 235K miles and still original, you got your money's worth out of it!

For info, the swirl valves are forced to operate and open/close a cycle, each time the key is operated The design intentions is to clear carbon from the butterfly's themselves. This is where the self diag system picks up the fact that the operating cycles if compromised or coming up short ,hence the code and the MIL light .
At this mileage, frankly the best remedy is to replace them if you want to keep the engine running at it should or designed to do.
There are work arounds to blot it out by programming, but I/We don't do that .
Dennis

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JlbSeattle said:

I’m wrapping my head around the work/money involved in replacing the manifolds. For the time being, I employed the resister trick in the 2-3 positions of the swirl motor wiring connector. My question is: am I doing damage to the sprinter running it this way?

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glsski said:

has anyone had the EKAS issue resolved under warranty with the extended emissions warranty. Since that warranty covers intake manifolds??

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