65aircooled

I also have this thread on mercedesbenz.org , if you read it there please disregard.

I am getting slapped in the face this week by my CDI. I have been nothing but nice to it and yet it keeps on throwing these tantrums that I was not expecting to have to deal with this early in ownership, although it is a used car way out of warranty so, anything goes.
Yesterday I went to the carwash to get it cleaned up. I drive about 6 miles round trip to a hand carwash that I've been happy with and going to for a while.
On the way there I went to overtake a car and there was no power, I floored the go pedal and it was like dead, same as pressing it 1/4, 1/2 or all the way.
I got the car wash, turned the car off, they cleaned it and then I got back on it and everything was back to normal. On the way back home I took the highway so I could give it a bit of a kick and it was peppy again. Then I took the family out to dinner and it did it again, so I stopped and turned it off and on and it immediately thru a check engine light. Once I got back home I hooked the OBD reader on, showed code P0404 Exhaust Gas Recirculation Circuit Range/Performance
I have been reading about this all day, different theories even outside this forum that even suggest a voltage discrepancy to the PCM or a short in the ground or positive going to the PCM (remember this)

All of the threads on any and all MB forums become a DEAD END, meaning not a single person that posted about this problem in the past 7 years have come back to post a fix or a resolution to the problem they had, thus the reason for this thread.

The factors I am taking into consideration are as follows:

1. Did my complete engine service (fuel filter, air filters, oil change) and I had the feeling that I had put too much oil based on the PDF manual I downloaded form the MB site. Then I rechecked my hard copy, 7.5L so it could have been correct, I didn't measure the oil that came out when I vacummed it because I dispose my oils at PepBoys and usually collect it in a 5 gallon bucket that I have set ip with a discharge valve when it is full. The day I did the oil change the car read "OIL LEVEL OK"
So thinking I may have overfilled the engine with oil thus possibly causing EGR problems, I took a bit more than a quart of oil out, then I checked the oil level and the car said "ADD 1 QT OF OIL TO REACH CORRECT LEVEL"
I though that was a good thing, so I went to auto part store and bought 1 qt, added 1/2 a qt and measured the level. Car now reads "OIL LEVEL OK" Drove a couple of miles and checked again, car reads "OIL LEVEL OK" Over a quart out, half a quart in and yet the car measures Ok?
So I guess 1/2 quart -/+ makes no difference to this engine or the measuring system is not all accurate? I will buy a dipstick to check from here on.

2. I raised the front of the car significantly yesterday to check the strut torque arm and ball joints due to a dead knock I keep hearing in my pass side on hard braking and small pot holes. Ball joint in the pass side is shot. So I put the car back down and then drove to the carwash... and that's when I experienced the first loss of power/limp mode.
Makes me think a hose to/from the intercooler may have been cracked or pulled? I quickly checked that this afternoon but it got dark on me so I could not do it right, I need to remove the front belly pan to have a better look.

3.Yesterday, after lowering the car back to the ground I took the engine top covers off to check the fuel filter clamps (the old ones were leaking when I did the fuel filter change) and then took a few minutes to do a little cleaning. I sprayed around some WD40 and got the EGR and connectors wet. I thought nothing of it, wiped it dry and put the covers back on.
Could a bit of WD40 on the EGR connectors have caused this?

So last two are the ones that are going around in my head the most. I know that ***** happens and so do coincidences, but it seems a bit too coincidental that after doing the above the EGR valve or something related to it -based on Code P0404- started acting up.
I took the EGR connectors off today and cleaned them with electrical contact cleaner but the problem keeps coming back.
By the way, it only seems to affect the car once it reaches normal operating temperature (80 degrees F)

Lastly, I am working on getting a STAR SENTRY system from a trusted source and should get it in the next two weeks or so, but until then I'd like to gather more info on the problem.

As always any and all info will be greatly appreciated!!!

E55Greasemonkey

Simple, you need to replace the EGR valve. Common problem on that motor. You should also have the dealership install the latest engine software for your car which addresses the EGR failing. Although the EGR valve may look easy to replace, it typically gets stuck in place with carbon. Some PB blaster, and giant pliers to twist it back and forth usually works, and you will destroy the old valve in the process.

The oil level sensors/cluster are also known to be not accurate. The best way to check the oil level is using DAS/XENTRY with the engine idling. About 8 quarts when changing the oil is close.

65aircooled

My next oil change will be using the DAS/XENTRY
As far as the EGR valve goes, I have read a lot today and still no clear consensus of that being the cure. The problem is that in most threads, CDI's and BlueTecs get thrown into the mix.
I may just bite the bullet and order a new EGR and then have the dealer re flash the computer.

E55Greasemonkey

12 years as an MB dealer diagnostic tech, and that's the first thing I would replace, if in fact that is what code you have. The OBD descriptions differ slightly from MB's code descriptions so I'd have to look it up. Matter of fact, there is a technical bulletin released by MB about your problem The EGR valve sticks open due to carbon buildup. Keep in mind a lot of things you read on the internet are posted by car owners, not technicians

Since your loss of power is intermittent, simply unplug your EGR valve, and drive for a few days..if the problem does not repeat itself within the usual time/distance limit then you'll know it's the EGR.

You own the last good diesel engine made my MB. Stay far away from the BlueTec.

65aircooled

I hear what your saying, didn't know you were an MB tech. As you said most of the advise in forums come from owners, I usually take it all with a grain of salt and then try to make a better educated decition.
One of the things that really ticks me off if the amount of ppl that ask for advise, get it and will not post back after getting the problem fixed. I am going to order a new EGR but want to fix my HP fuel pump first to rid of the leak, clean the mess that is has made and then tackle the EGR.

Thanks for the advise!

E55Greasemonkey

Good luck and feel free to PM me since I will probably loose this thread over time.

65aircooled

I will PM you for sure. Thank you!

CaptMike

Hi E55Grease

I don't have a code yet for my problem that occurred today but wanted to try to get a head start as I will be towing my 2003 E320 to my shop in the morning. I was driving it all day without a problem with start ups and shut downs and came home and shut it down. About 2 hrs later started it up and drove it about 2 blocks and turned it off again. When I attempted to start it back up after that last shut down...about 2 mins....it ran rough and stalled. Tried several more times to start it up and it would again run rough then shut down. On one of the last start attempts it did start and was actually accepting some throttle input increases and would not die at idle power so with that I started driving about 40mph. About 2 miles later it would not take any increase in throttle but would run ok when I backed off the throttle a bit...until I came to a stop sign and it then shut down. Had it towed home.

Any suggestions?

Thank you

65aircooled

I see that you have a 2003, my solution won't apply to your gas engine but I'd try the CPS in your case first.

JohnKhach

CDI P0404, you can easily clean the EGR Vale without braking it, remove the wire connector, tow holding bolts gently clear the oil dip stick tube try to turn the valve left & right it will turn and brake carbon build up with little effort after removing clean excessive carbon from the valve in front of the actuator motor plastic cover has two little tabs gently prty out and pull the cove up-rite you will find crank type lever clean carbon with solvent, with compressed air blow out the remaining then move the levet to open valve apply carb cleaner till it moves freely lube the stem with penetrating oil and work it out so it will re-seat on its own that will solve your EGR problem

CaptMike

Ended up replacing fuel pump, sending unit, and all related gaskets,

rususerghei1985

hello there. I got the same problem. Engine light on and code p0404 and power loss... did clean the egr... reset the engine light. At the end didn't work. BUT.... THE PROBLEM DID NOT STARTED WITH P0404. It started with turbo fault. Changed it. In 2 months actuator gone bad. Engine light on and OBD 2 CODE p0244.... ordered a refurbished actuator and I changed it.... after 3 days engine light on and code p0404 EGR. Mentioned above what I did.... and I also observed something else.... the car drives perfectly until she gets at the working temperature.... and then happens the power loss. Switch off and back on. My car drives perfectly again. ... kinda got lost what to do and where to look. I really wish you guys help me.

U406

I had a similar problem on my G350 (OM642-866 engine). It started after the workshop changed the oil-to water cooler due to an oil leak (Mercedes knows that there is a faulty o'ring, but leaves the charge of this change to the owners...)
To change this component they had to remove the turbine, the injection and all the stuff that are over the engine, because it is located at the abse of the "V" of the engine..
when I picked up the car after two days, I noticed that when the engine became warm (90°C) and under load, there was a strange noise like an air (or gas) leak. You know, like a razz.
The mechanics start to say that it is the turbine, but I absolute don't believe it is. It has only 90000Km and it was always well used and maintened.
Yesterday I was on the highway and suddenly I lost the pressure. the engine start to run without the turbocharger without the MIL light on. After a couple of start up during the day I finally had the MIL light on.
This morning the mechanics read the fault codes (I saw a problem with the left EGR valve) but it continued to state that the problem is the turbine. I read the fault codes with my OBD2 reader and it is confirmed a P0404 code (EGR Control Unit fault).
I am sure that the turbocharger is fine... I will look to the EGR valve.

Just a question. Do you had a similar noice (the one like a razz) during your events?
Thank you!

isthisit

JohnKhach is correct. You can clean and lube the egr mechanism. The proper fix is to replace the egr valve but i've been cleaning my egr for couple of years now ( once a month or so) and it's fine.
There is no need to remove the egr. just the semicircular plastic cover on top of the Egr. Brush the soot off and pray some high temp lubricant on the mechanism and more importantly the plunger stem. move the mechanism back and forth to work the lubricant down into the plunger shaft. Let me know if any of this doesn't make sense. good luck!

U406

Thank you! I did.
The valve is working perfectly. I checked all the EGR lines and everything is fine. I try to replace the turbocharger in order to ascertain if it is the problem. I loaded a small video with the noise that I hear. It seems to be at about 2000Hz (more or less).
If someone is interested to hear it, please go to We Trasnfer at this link (It will last from one week from now on, but you can ask the file to me if needed):
https://we.tl/t-rY4TnuO3pk

ChrisFalconer

I now have the same issue!
original code was crankshaft position sensor.
attempted this and ended up paying garage £400 labour to fit the sensor.
Collected from garage all good, parked up. Few hours later went to shops and on way back puff of smoke and EML!!
new code is EGR valve. I plan on replacing with a new unit, but is there any this else anyone can suggest is worth doing at the same time?

last of production 2009 clk 220 cdi sport