w204 220 CDI New EGR Valve and now DPF Regen Limp mode problems

[220problem]

Hello, this is my first post and I'm glad I found this site.

My mechanic has now been servicing my car for the last 5 years. On my w204 2012 cdi 220. 125k motorway mileage. Problems I have had so far prior to this issue.

I remember earlier in the year I had a turbo boost problem and then I found it to be a hose that needed replacing.

Now I was having constant problems with my car going into Limp mode when driving half a mile down the road in the cold, it would judder and go into limp mode.
Sometimes I would stop, wait a minute and start the car again, this sometimes took it out of limp mode.

Then I bought a diagnostic tool and I had a various range of messages for example:

P0697 Sensor Reference Voltage C Circuit / Open (I know this is not a STAR code)

So my mechanic said he diagnosed the problem with it being a wiring problem in the harness. (sounded a bit odd to me, but the problem was fixed no more limp mode)

Now here is what happened;

I kept getting the same problems again mainly car going into limp mode and temperature flucating, never high but always towards the low 40 to 60 and sometimes back to 90. I bit the bullet and I was skeptical of this, but I took it to Mercedes for a full diagnostic test and they said EGR code appears.

I've changed my EGR now, and then my mechanic kept the car to test out for 2 days more. He said he took it on a long run which i saw 56 miles on my dashboard when I picked it up. Then the next morning I start the car, I get a error about DPF Regen did not complete, something along those lines, but the car is stuck in limp mode.

This morning I left it on for 1 hour and the car was a little jerky, it was out of limp mode but engine light still on. Took it to the mechanic and I got a code P2459 Diesel Particulate Filter Regeneration Frequency and I couldn't remember the other code when I was checking his machine but then I remembered it was the same code as before.

P0697 Sensor Reference Voltage C Circuit / Open (I know this is not a STAR code)

New EGR is Mercedes part
Wiring Harness Job looks like it was not completed or done properly

Would a EGR cause a DPF Regen problem, and if I could get some advise now what to do next, my mechanic is going to try a new DPF sensor. But I am hoping somebody who has had this problem can help me resolve it, because this all together has costing a lot of money

 

[Tonygw]

Friend had similar issue and it turned out to be the dpf sensor, not a big job. But worse case I suspect the dpf could be blocked.

But yeah really needs an MB indy not a main dealer to have a look, the indy (in my experience) is willing to spend a little more time with STAR to get to the route of the problem.

 

[220problem]

Friend had similar issue and it turned out to be the dpf sensor, not a big job. But worse case I suspect the dpf could be blocked.

But yeah really needs an MB indy not a main dealer to have a look, the indy (in my experience) is willing to spend a little more time with STAR to get to the route of the problem.

Thanks Tony for replying, I see you are in Leicestershire, do you have a mechanic you can recommend using?

 

[Tonygw]

Certainly do

I trust these guys MB Automotive - Mercedes-Benz Specialist Loughborough

Very very honest and very very knowledgeable. Well worth getting them to have a look. The only problem is, people know about them and they are soo busy!!
Let us know how you get on.

 

[220problem]

Certainly do

I trust these guys MB Automotive - Mercedes-Benz Specialist Loughborough

Very very honest and very very knowledgeable. Well worth getting them to have a look. The only problem is, people know about them and they are soo busy!!
Let us know how you get on.

Thank you I'll check them out, bit of a trek from my neck of woods, I want to update the thread after I've resolved the problem, so others do not get mislead by other mechanics.

 

[Smart320]

You could also try Mercland in Nuneaton, they are forum sponsors , specialise in MB , very good and reasonably priced, I have bought an ML from them and used them for servicing and my family live nearby and report very good service on their ML

 

[220problem]

You could also try Mercland in Nuneaton, they are forum sponsors , specialise in MB , very good and reasonably priced, I have bought an ML from them and used them for servicing and my family live nearby and report very good service on their ML

Thank you, I'm literally at the point I'd pay a lot of money just to have my car back how it was before, like most people I guess. Thanks I'll check them out.

 

[220problem]

Hi all, so i finally got my car back and thought I'd update you all.

The mechanic has cleaned my DPF, not by taking it off but by putting the DPF cleaner down the DPF sensor hole and left it over night. Apparently next morning or afternoon he rev'ed out all the grey/ black smoke and it is now fine no DPF Regen code showing.

Then next problem when he took it for a test drive, throttle body actuator was showing a problem, then I'm blindly hearing this on the phone, and something did not sound right at all.

Genuwine mercedes benz throttle body actuator fitted, now a test drive. Problem with Low Boost Pressure. (Going mad here)

They checked the wiring harness and said wiring looks fine. Then i get a call saying it was a wiring issue, i'm sure they cut the ends of the wires that go to the ECU and plugged them back in, all the fault codes have gone, no issues.

Lucky for me, this was not a case of needing a new ECU, new wiring harness and so on.

To those that commented thank you for your support!

 

[merc estate]

We all hope thats the end of it for you.

 

[Basa96]

Hello, this is my first post and I'm glad I found this site.

My mechanic has now been servicing my car for the last 5 years. On my w204 2012 cdi 220. 125k motorway mileage. Problems I have had so far prior to this issue.

I remember earlier in the year I had a turbo boost problem and then I found it to be a hose that needed replacing.

Now I was having constant problems with my car going into Limp mode when driving half a mile down the road in the cold, it would judder and go into limp mode.
Sometimes I would stop, wait a minute and start the car again, this sometimes took it out of limp mode.

Then I bought a diagnostic tool and I had a various range of messages for example:

P0697 Sensor Reference Voltage C Circuit / Open (I know this is not a STAR code)

So my mechanic said he diagnosed the problem with it being a wiring problem in the harness. (sounded a bit odd to me, but the problem was fixed no more limp mode)

Now here is what happened;

I kept getting the same problems again mainly car going into limp mode and temperature flucating, never high but always towards the low 40 to 60 and sometimes back to 90. I bit the bullet and I was skeptical of this, but I took it to Mercedes for a full diagnostic test and they said EGR code appears.

I've changed my EGR now, and then my mechanic kept the car to test out for 2 days more. He said he took it on a long run which i saw 56 miles on my dashboard when I picked it up. Then the next morning I start the car, I get a error about DPF Regen did not complete, something along those lines, but the car is stuck in limp mode.

This morning I left it on for 1 hour and the car was a little jerky, it was out of limp mode but engine light still on. Took it to the mechanic and I got a code P2459 Diesel Particulate Filter Regeneration Frequency and I couldn't remember the other code when I was checking his machine but then I remembered it was the same code as before.

P0697 Sensor Reference Voltage C Circuit / Open (I know this is not a STAR code)

New EGR is Mercedes part
Wiring Harness Job looks like it was not completed or done properly

Would a EGR cause a DPF Regen problem, and if I could get some advise now what to do next, my mechanic is going to try a new DPF sensor. But I am hoping somebody who has had this problem can help me resolve it, because this all together has costing a lot of money

Buy a v6 3.5 deisal w212 you will enjoy a Mercedes as it should be all them 4 cylinder jobs have loads of problems