Disabling EGR

[Alex Crow]

MAF sensor is always used, the EGR mod lowers the MAF sensor voltage with EGR operation, but MAF sensor still needs to work.

 

[bob 6600]

If you do buy a MAF, buy a genuine one. Either from MB or yours should be the same as mine, Pierburg. They are currently just under £48 from ECP

 

[Alex888]

Thanks a lot guys.
Tested my MAF today and voltage 12v and 5v comes in but there are zero voltage from signal cables.
So I am going to buy MAF.
Bob 6600 can you please give me MAF's part nuber that is good to put to I can find it in my country?

 

[Alex Crow]

Thanks a lot guys.
Tested my MAF today and voltage 12v and 5v comes in but there are zero voltage from signal cables.
So I am going to buy MAF.
Bob 6600 can you please give me MAF's part nuber that is good to put to I can find it in my country?

Hi, if you have Mercedes dealer near, ask for price.

Otherwise just make sure it is a Pierburg/i2s MAF sensor and it will be fine... http://www.ebay.co.uk/itm/PIERBURG-...arts_Vehicles_CarParts_SM&hash=item27d441016b

 

[bob 6600]

here's another from KMS, part number in the listing

http://www.ebay.co.uk/itm/200940139825?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649

 

[Alex888]

Thanks a lot for help!
MAF replacing helped.
I bought new one PIERBURG per around £44.
Works perfect. I like this car

 

[bob 6600]

Flaps do not cause so many problems on these engines, and as they are working now, I suggest you leave well alone.

Looks like I had to open my big mouth!

Having a problem with STAR communicating with my vehicle so thought I'd check everything again. The bar on the motor for the flaps is connected but now does not move! Engine was warm, but should this matter?

Checked connection and it's fine

 

[oldbeaver]

Mercedes Diesel turbo mods

The MAF is in the cold intake the EGR enters further downstream. the MAF then monitors the reduced cold intake when the EGR valve admits hot recirculated gas.
The biasing circuit drags the MAF voltage lower when the EGR signal line goes low.

Hello Dieselman, I will do yr mod of EGR "inhibitor" and see how it performs.
However, I like to test all my mods very rigorously. For that purpose, my first Project is to install a Trip Computer in my 1993 300D turbo, so I can see an objective instantaneous response in mpg and power (both interest me).

In that way I am lacking of the EDS exact circuit of my car, which engine is a OM603 6L. I am attaching a picture of it.

Once I have my Project ready, I will share with the community of MBZ diesel ownwers of 1987-1995 models.

I think my car is asiatic as it has a maintenance label in asiatic characters, but I cannot say if they are from Japan, China, Singapur, or other country. The car is LHD.

You can send me an email if you want.

Looking frwd for yr coments,

Oldbeaver

 

[Alex Crow]

Hello Dieselman, I will do yr mod of EGR "inhibitor" and see how it performs.
However, I like to test all my mods very rigorously. For that purpose, my first Project is to install a Trip Computer in my 1993 300D turbo, so I can see an objective instantaneous response in mpg and power (both interest me).

In that way I am lacking of the EDS exact circuit of my car, which engine is a OM603 6L. I am attaching a picture of it.

Once I have my Project ready, I will share with the community of MBZ diesel ownwers of 1987-1995 models.

I think my car is asiatic as it has a maintenance label in asiatic characters, but I cannot say if they are from Japan, China, Singapur, or other country. The car is LHD.

You can send me an email if you want.

Looking frwd for yr coments,

Oldbeaver

Hello,

Your car probably has no MAF sensor (not in the picture), and the EGR mod is not applicable to your car.

HTH

 

[Crouchie]

EGR Mod

Hi all

I have completed the modification of the inlet manifold on my ML 270 Cdi and have made up the shunt using the components suggested by Dieselman. I have installed the shunt but still getting limp mode when I disconnect the plug from the EGR transducer.
I just want to confirm that you are supposed to disconnect the plug once the shunt is installed??
I have checked my wiring and have had an ohm meter on either end of what I think is the maf wire to the ECU and I have the right one. I have done the same with the other two wires but still getting the dam limp mode.
I have also made up another shunt and tried that.

Any ideas??

 

[stumo]

Hi all

I have completed the modification of the inlet manifold on my ML 270 Cdi and have made up the shunt using the components suggested by Dieselman. I have installed the shunt but still getting limp mode when I disconnect the plug from the EGR transducer.

What exacrly do you mean by "modification of the inlet manifold"?

Does limp mode clear if you plug the egr transducer back in? (Its supposed to be disconnected, but plugging back in can help diagnose why you are in limp)

 

[jsawick]

I have done the same thing, and the Limp mode returned.
I have reconnected the EGR cable, (as I have the EGR manifold blocked) and all errors have vanished, and the mod is working as intended.
Not sure if the EGR valve is trying to do anything, but it appears, that if it is disconnected, the ECU will detect it and go into limp mode.
Perhaps disconnecting the EGR and placing a shunt across is as described in earlier postings would do?

 

[oigle]

I don't mean to be critical but the shunt, fitted properly, is working perfectly in hundreds of 270 motors.
You have done something wrong and you need to fully check out all the connections used. Be very sure that the correct wire from the maf connector is being used as that can be easily done wrongly.
When fitted correctly, the egr transducer connection must be disconnected. The use of a plate to block the exhaust is of no consequence either way. The valve should never open, thus creating its own block. The vacuum tube must remain connected to the transducer or alternatively blocked off with a suitable ball bearing.

 

[ex4x4]

Hiya all -i'm newbie on this forum, but hope to contribute wherever I can.
I've been following this thread for a while and took the plunge. I've made up my shunt from a few bits in my toolbox and began tracing wiring on my 2005 CLK 270CDi (C209)
The EGR wires are quite straight forward - and present themselves as a twisted pait in ECU enclosure.
However the MAF is a tad confusing.
I believe the signal wire is always on the terminal 5 of MAF plug, and should show a swing of 2-4Vdc when engine rev'd. However when I've tested my term 5 output ( connect to MAF and probed through insulation) _ achieving a 0.5Vdc swing from 0.5 - 1.0 V - is this correct?
More confusing still - the wire on MAF plug is BR/WHT yet when belled back to ECU it has swapped colour to YL/WHT - (pin 24 on plug 4).
Is it normal for wiring to change colour code mid run?
any help greatly appreciated
Alistair

 

[barry jones]

would this work on a 2006 S320 CDI? if so, can anyone offer what I need to do to bypass the EGR

 

[kew1]

EGR bypass and flaf removal

Shortly after buying my ML270 I noticed drips of oil on the drive, I had a look under the engine and the LH side of the engine was covered in a thick black oily sludge.
I read the info from dieselman and others and decided that I was going to get rid of the flaps in the inlet manifold and stop the EGR valve working.
I will admit that it was a lot of work getting the manifold off and on but it is not difficult just lots of parts to remove and fit.
Today I completed the work and took the car for a drive, what a difference, it seems as if the engine has grown a sixth cylinder.
The only problem I have now is that my smokescreen doesn't work anymore when the police are following me.
I would recommend this to all diesel drivers and thanks to all of you who have contributed to this thread, without you I'd still be making a mess on the drive and in the atmosphere.

 

[darellpa]

MAF sensor help

Hi All i have come across this thread whilst looking up a problem with poor boost/performance from my TD? I have been going through all of the possible causes and in the process i removed the MAF sensor "to inspect only" and there seems to be a part missing it is the component that looks like a small diode and clips in to the 2 metal clips? My question is, what does this do and is it required and is it possible to get this part separately as the MAF seems in very good condition? I will be looking into bypassing the EGR this looks like a great mod

 

[Alex Crow]

Hi All i have come across this thread whilst looking up a problem with poor boost/performance from my TD? I have been going through all of the possible causes and in the process i removed the MAF sensor "to inspect only" and there seems to be a part missing it is the component that looks like a small diode and clips in to the 2 metal clips? My question is, what does this do and is it required and is it possible to get this part separately as the MAF seems in very good condition? I will be looking into bypassing the EGR this looks like a great mod

Although you may see a place where the component could be fitted, it is not on yours.

 

[bob 6600]

Question for you experts....

My EGR has been diagnosed as faulty with a STAR diagnostic so it has current and stored fault codes. These were cleared but will obviously come back.

Ok so rather than replace the EGR valve, I have done the mod but the car behaves in exactly the same way (limps intermittantly). Do I need to get the faults cleared again now the mod is done?

 

[Myros]

bob, are the symptoms exactly the same,

provoked in the same way? It sounds as though the mod isn't fixing matters. Have you blocked off the egr actuating mechanism? Is the egr closed?

what fault codes are you getting, and what exactly are the symptoms?
sorry to sound like Dr Kildare here, but once the mod is done, connected properly, and all the fiddly bits restricted or disconnected, then the car should run like a rocket.