CLK 320 EGR Removal?
Thread Starter
Member
Joined: May 2011
Posts: 165
Likes: 4
2005 CLK 320
CLK 320 EGR Removal?
I have a CEL on with a P0400 EGR code. Not affecting drivability but I thought I’d get it taken care of over the weekend. In the past, on other cars, I have been able to pop it off and clean it with success.
After taking off the air cleaner, I could see that this wouldn’t be a straight-forward job. I searched for How-To’s but couldn’t find any, but I did find several links showing that a P0400 could be other things in the system, rather than just the valve, so I backed off taking the fuel rails etc off, just to find out that the EGR is OK.
Firstly, is there a How-To description that anyone has seen on removing the valve?
Secondly, how common is an actual failure of this valve, versus a leak somewhere. It is an 05 with 62k on it, if that is relevant
After taking off the air cleaner, I could see that this wouldn’t be a straight-forward job. I searched for How-To’s but couldn’t find any, but I did find several links showing that a P0400 could be other things in the system, rather than just the valve, so I backed off taking the fuel rails etc off, just to find out that the EGR is OK.
Firstly, is there a How-To description that anyone has seen on removing the valve?
Secondly, how common is an actual failure of this valve, versus a leak somewhere. It is an 05 with 62k on it, if that is relevant
Member
Joined: Sep 2014
Posts: 176
Likes: 6
From: Sarasota area, FL
Current: 2020 E450 with self-driving capability
I'm afraid I don't have a direct answer to your question, but I went after my EGR line after reading a bunch of posts on other boards about it becoming clogged with carbon and throwing the P0400 code as a result. My car is at 145k miles, so I expected to find it clogged, but it was actually fairly clear and the P0400 persists. I haven't tried taking off the valve yet, but that looks pretty straightforward; just a couple of bolts.
As to the EGR line, I found that there was no freaking way to get at the nut connecting it to the EGR valve without taking off the passenger's side valve cover. Once I did that I could get the nut loose but couldn't separate it from the EGR valve. Ultimately decided to cut the line, which allowed me to unscrew it.
I'm now waiting on vacuum lines so I can replace all of those, and if that fails I'll replace the EGR valve itself.
As to the EGR line, I found that there was no freaking way to get at the nut connecting it to the EGR valve without taking off the passenger's side valve cover. Once I did that I could get the nut loose but couldn't separate it from the EGR valve. Ultimately decided to cut the line, which allowed me to unscrew it.
I'm now waiting on vacuum lines so I can replace all of those, and if that fails I'll replace the EGR valve itself.
Super Member
Joined: Mar 2010
Posts: 684
Likes: 14
From: Lebanon
2007 BMW 550i
I had a P0400 code as well. I didn't remove the valve cover to get to it. in fact we had to remove the fuel rail and it came out. taking out all the screws is only half the work. actually removing the EGR is a PAIN!! take a look at pictures on google or somewhere, it twists inside the manifold; but it is doable. But the truth is even after cleaning my EGR, which wasn't that dirty, the codes persisted. I eventually noticed 70% of my vacuum lines were shot, included the one on the EGR itself. So its worth a look. For reference; that did solve my problems. I have no idea why my computer gave out an EGR code, when it was 2/3 of my vacuum lines that were bad. My mechanic told me its uncommon for the EGR valve itself to fail; but everything is possible.
Last edited by DanielFD; Jan 20, 2015 at 09:10 AM. Reason: more info
Thread Starter
Member
Joined: May 2011
Posts: 165
Likes: 4
2005 CLK 320
Well that's precisely my concern; that I would remove and clean it with no improvement.
I'll recheck my vac lines then
Wodeshead - did you find a hole in any of the lines or are you just pre-emptively changing them out?
I'll recheck my vac lines then
Wodeshead - did you find a hole in any of the lines or are you just pre-emptively changing them out?
Member
Joined: Sep 2014
Posts: 176
Likes: 6
From: Sarasota area, FL
Current: 2020 E450 with self-driving capability
I didn't have the stuff to check the vacuum lines, and made the mistake of believing that all these other posts about clogged EGR lines (from EGR to intake manifold) so I just went ahead and replaced it. I've got the vacuum lines on order now. The tricky thing seems to be what diameter they are, and they're ordered by the meter so I just ordered a few meters of each possible diameter.
Super Member
Joined: Mar 2010
Posts: 684
Likes: 14
From: Lebanon
2007 BMW 550i
my mechanic had a couple of vacuum lines that were the right width taken from a Jaguar XJ and a 1985 300ce haha damn those old cars had high quality parts! the vacuum lines are steel braided on the inside!! Also worth noting these is a vacuum lines that runs out the bottom of the intake manifold from the front. You'll have to remove the secondary air pump, its really just one nut and a connector, then you'll have easy access to most the lines and the vacuum line under the manifold. if that line is shot, be prepared to plug in a double sided connector for the vacuums to connect a new vacuum line because that line runs into the bottom of the manifold and is connected on the inside! no way to get to it!
Member
Joined: Sep 2014
Posts: 176
Likes: 6
From: Sarasota area, FL
Current: 2020 E450 with self-driving capability
Thanks. Yeah, I've been reading up on that on the Pelican Parts site. It could also be the changeover valve, from what I understand.
Link to changeover valve: http://tinyurl.com/ml8glsz.
Link to air pump check valves: http://tinyurl.com/odnbrv5
Link to air pump remove/replace: http://tinyurl.com/oyhypmc
I live in Florida where there's no smog inspection, so I'm not worried about emissions testing but I would like to get rid of the P0400 code.
Link to changeover valve: http://tinyurl.com/ml8glsz.
Link to air pump check valves: http://tinyurl.com/odnbrv5
Link to air pump remove/replace: http://tinyurl.com/oyhypmc
I live in Florida where there's no smog inspection, so I'm not worried about emissions testing but I would like to get rid of the P0400 code.
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Super Member
Joined: Mar 2010
Posts: 684
Likes: 14
From: Lebanon
2007 BMW 550i
Yup very possible, when my car had the code it would show up as P0400 on a generic OBDII scanner but on STAR I had an extra error "pressure sensor value -1" something like that. I didn't give it much attention until after I had taken apart the EGR and found it not too bad off. turns out the vacuum line that connects to the back of the Pressure sensor was ripped of completely. which then lead me to check all of the vacuum lines and start replacing.
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Super Member
Joined: Mar 2010
Posts: 684
Likes: 14
From: Lebanon
2007 BMW 550i
Thought i'd update the thread! Stupid $#&%*^@#$@ING EGR. The engine light is back on in my car. Plugged in STAR and its code P0400 again. this time without any other codes. So I did some testing through STAR. where you actually actuate the EGR and its supposed to cause rough running. The first time it was actuated the car ran rough(working) but when I turned the EGR off the car didn't stop running rough(which means the EGR is getting stuck). After turning the car off and on again, I tried again and the EGR wouldn't actuate on anymore. Then again I tried and it did actuate and it stuck on again. So most likely its shot. My mechanic and good friend told me its better we test all the systems related to the EGR before swapping it out. It was late in the day when we were testing it. So when I get the time to tackle it I'll keep you guys posted.
