2011 ML 350cdi Code P0405

[Jam60]

Hi Everyone,
I have returned to the MB fold after having a couple of years with another make but have recently got an ML and initial thoughts were impressive however my problems are maybe just starting? Hope not.

My ML starts and runs fine for about 10 mins, after it warms up it appears to have no turbo boost and is very lethargic but usually No MIL light. The only time it put on the MIL light I plugged in my hand held scanner and it displayed the code P0405. On investigation this suggests EGR valve. On chatting to my Merc specialist He states that this is a bit of a rarity and can also be a pig to remove sometimes (He can't look at it for a week). I have studied how to remove the EGR and clean it but am having 2nd thoughts as this may be a waste of time? However I would appreciate anyone's experience of the above issue and advice?

 

[mioba]

If you are using a generic reader, I would get a second opinion.
Going through the efforts to remove a faulty valve to clean it, only to put it all back together and find it doesn't work will annoy you. That said they do clean up well.
Your call, cost of new v being confident in a clean up.

 

[Jam60]

Just a quick update. Had my ML in for diagnosis at Merc specialist Good news & Bad. I was correct in my original diagnosis it appears to be The EGR valve. Sadly they are a bit like rocking horse poo at the moment ie unavailable from Mercedes UK at the mo.

 

[ajlsl600]

That's cos of dtf and many defective. Recycling exhaust n other combustion gases thru electric, electronic controlled valve a sure remedy for. Expensive disaster. Plastic inlet manifolds another.

 

[Wighty]

Just a quick update. Had my ML in for diagnosis at Merc specialist Good news & Bad. I was correct in my original diagnosis it appears to be The EGR valve. Sadly they are a bit like rocking horse poo at the moment ie unavailable from Mercedes UK at the mo.

Take it out and clean it buddy , I do mine every year . 30 minutes work maybe .
This may help

Egr valve clean up | Engine

Took the egr valve off yesterday, no issues or codes just some preventative maintanance. the soot coating was a little thick and sticky, so i hit it with some cleaner and took my time going over it several times. Picking up a new seal washer for it from merc tomorrow with a few other things...

forums.mbclub.co.uk

(it’s from the other side )

 

[Wighty]

This was the one I was looking for

OM642 EGR clean

Seen mention recently that the back of the EGR can be removed to check/clean the mechanical inside workings of an egr . Even though I remove mine yearly to spray the gunk off I had never taken it apart before so blaming the sunshine I cracked on with the attempt . Two bolts to remove the EGR ...

forums.mercedesclub.org.uk

 

[Jam60]

Thanks for the info Wighty. Merc man said He took it off & cleaned it, also said it then started leaking water which He repaired. Gasket I presume? Going to bite the bullet & get it mapped out as Merc can't give a timescale of EGR availability.

 

[Jam60]

Out of curiosity does anyone have a part No for a water cooled EGR valve gasket please?

 

[supernoodle]

Isn't P0405 Exhaust Gas Recirculation Sensor “A” Circuit Low? That sounds like the feedback from the position sensor is below normal range rather than anything mechanical. Open circuit would give a circuit low too.

 

[Jam60]

That's what my scanner diagnosed A circuit low wasn't sure if mine was accurate hence taking it to s Merc specialist who diagnosed the EGR pooped.

 

[mioba]

I wouldnt map it out. Thats just circumventing the issue.
A clean up and your car is in order.
Just my tuppence.

 

[Jam60]

As stated previously the EGR is at fault and looks like availability is an issue at this time so mapping it out is my only choice at present.

 

[Jam60]

Update: Had it remapped inc programming the EGR out. Done over 500 miles and have to say I'm impressed. Cheaper option than the Unavailable EGR valve, smoother & more powerful delivery when required and improved fuel consumption indicated but I'm sceptical about the reading???
However I am pleased with the results and saves running around in limp mode with the potential to bugger the dpf as well!

 

[ajlsl600]

Spot on...