Disabling EGR

[oigle]

if i comprehend correctly, i should build the circuit(like in the photo), then identified the individual wires correctly, the strip the wires insulation and solder the circuit onto it like in the scratched drawing as below ?

how to use the multi-meter to determine the wire is the correct before stripping the wire?
can anyone explain?

By using the multimeter in its resistance mode, you will find the 2 points with 0 resistance and have thus identified the wire correctly.

Ian.

 

[PeterSk]

Hi
On first you must switch your multimeter to measure resistance or short cut.Then attach the meter to the bearded one end of the wire in the ECU and the other at the other end with MAF or vacum transducer. Multimeter starts beeping or showing minimal resistance when measuring a single wire. When you mistake and dont measure a single wire your multimeter will show maximum resistance.it is bas to write but simply to do...

 

[Kispek94]

Hello all!

Please help me! I have a 98' c250td with maf and egr monitoring.
I tryed disablig.. connect the ecu 21(yellow/blue) maf5 and the egr vacuum activator: ecu35 (white/gray) whit 470ohm resistor and 1n4007 diode but dont work..
Limp mode p1403 error code

Please anyone show for me a correct wiring diagram for disabling.

Thank you!

Sorry, i am hungarian, i dont know english very well!

 

[Kispek94]

Om605 egr

Hello all!

Please help me! I have a 98' c250td with euro3 engine, maf, egr monitoring and cut off valve.

I tryed to fix the egr problem but doesnt work. I connected the wires : ecu21 and ecu35 and maf5, egr vacuum valve with 470ohm resistor and 1n4007 diode.
The fault code is still avaiable . P1403

Please help how to fix it. Anyone have a correct wiring diagram for the fix?

Thanks!

Sorry, i am hungarian my english is bad

 

[Kispek94]

C250 td egr





Is correct for me?

 

[blobbt]

2002 w220 320 cdi

Hi am looking to disable the egr on this car, can someone point me in the right direction?

Not sure of pinout's on ECU and how you find them

thanks james

 

[Dogfish]

So, on a W203, using yellow goes to MAF and green and red to transducer. Still can't work out which transducer wire is which! (brain freeze).

I assume using a multi tester with ignition on I should find the +12v and connect red to this and green to signal.

Sounds simple, is it that simple or am I overcomplicating it?
Don't want to fiddle with ecu so wiring direct is the way I want to go initially.
I should have got this sorted months ago but been procrastinating.

 

[bob 6600]

The wires on the transducer will match the wire colours on the ECU plug. Pin numbers are normally the same across the same model, colours may not be

 

[om613]

Hello all!

Please help me! I have a 98' c250td with euro3 engine, maf, egr monitoring and cut off valve.

I tryed to fix the egr problem but doesnt work. I connected the wires : ecu21 and ecu35 and maf5, egr vacuum valve with 470ohm resistor and 1n4007 diode.
The fault code is still avaiable . P1403

Please help how to fix it. Anyone have a correct wiring diagram for the fix?

Thanks!

Sorry, i am hungarian my english is bad

Your car has the OM605 engine which doesn't have a MAF, only a MAP... hence this approach is the wrong one.

Just block the EGR flexi-pipe or plug the vac line with something.

Or have you fitted some other engine? The C250 td OM605 is not Euro 3.

 

[vadimlars]

Hey. I apologize for my English, I translate through a translator. Prompt please circuitry to disable the EGR for Mercedes sprinter 216 CDR, om 612 engine 2000 model year. Thank you so much

 

[Maul]

SUCCESS

Hi Guys
Just finished the EGR shunt today. WOW. What an amazing experience. It's like I'm driving a different car.
Lots more low end torque and more important, ZERO black smoke:-D

From the bottom of my heart, THANK YOU dieselman, for sharing this with all of us. And thanks to all of the guys that have piched in with help and good ideas in this massive thread.
And now I think I'll go for a drive...

Greetings from Denmark

 

[Buckts.74]

Does anyone know how to stop the egr valve from bleeding exhaust gases, after the electrical delete has been done? as in stopping the valve from being pushed open by exhaust pressurel. Also mine still makes that weird vacum noise when the engine is shut down ( electrical connector is unplugged and taped up ). Is that normal?
No error codes and car is running fine after electrical disable.

 

[oigle]

Just tap the valve piston home properly and it shouldn't leak. Pressure will NEVER open the valve. Suggest your weird vacuum noise may not be related to the egr unless you have left the vacuum line attached to the transducer and it has a diaphragm leak. Plug the vac tube with a ball bearing. Yes, leave electrical connection unplugged and tape it up for protection.
Ian.

 

[arch50]

hi guys a bit late with this but it worked great on my 2002 w203 270 cdi the smoke level has really dropped thats to dieselman for all the hard work oh and no codes !!!!
your archie

 

[Rustking]

Hi! I'm new to this forum, but I alredy saved a lot on picking up the mods from here! So Thank you!

Now unfortunately I have a problem! So I hope for some help here! About 5 years ago I did the modification to bought the EGR system and the M55 flap motor. Since then I have driven 80000 happy kilometers! Lately the MAF startet to fail, and I ordered an exact identical unit of pierburg brand. While wainting for the new MAF to arrive, I had the chance to modify the exhaust by emptying the catalysts. Was actually driving around for a few days with no exhaust at all, as a wainted for new clamps to arrive. New MAF shows up, and I'm amazed of how well the car now runs! This good feeling is then sadisticly taken away from me as I have to stop at an intersection, and I find out that the car limps and throws faultcode p1403 if the car idles for more than a few seconds.

Now, I have checked all the wires, changed the resistors and diode, soldered all connections, but problem still there.

I never got to test the car with no cats and the old MAF still working, so I question if the low exhaust back pressure, is the cause of this.

Help is much appreciated!

 

[oigle]

Perhaps your new MAF may be faulty. Cleaning out the CAT should not hurt anything. Maybe try another MAF or at least get it checked for operating within tolerance.

 

[Rustking]

I still have trouble with my moods. 3rd time trying to figure this out! Did the wires one more time, this time cut out the wire going to the transducer and soldered in the 1K resistor direct. Then the diode and the 470 ohm, with a wire T splicing to the yellow and white Maf to Ecu wire.

The yellow wire from the MAF is about 2.31v @ idle and rises as I rev the engine, without the resistors connected. I'm getting about the same with the resistors fitted. I wondering a bit about that. I should be able to se a slight V drop? Battery voltage @ idle is 14.75V. Engine stopped, battery is 12.86V. I use 2 shitty 20€ multimeters. Unfortunately no fluke meter.

Still p1403 after idle for more than about 5 sec. But if i get load on the engine, 1500 rpm is enough,it, does not limp, and seems to go on as it should.

Nowhere to test a MAF where I live, so the only option is to order anotherone if this one is bad.

Maybe the voltage regulator is defective and causes this problem, as 14.75V seems a little high to me? Any ideas? As always any advice is appreciated!

 

[oigle]

Thought you had 80000km of happy motoring since doing the egr delete......why are you doubting that mod now? Unless a resistor or diode has failed or the wiring connectors have failed, you should not be getting an issue there. 14.75 is too high but your multimeter may not be reading correctly. Try a different one. Should be max 14V. Your problem does not sound like a maf issue - it sounds more like an egr problem so you do need to check the above. The egr is supposed to open at idle after a preset interval before modification. Think you need to get a good indi to have a look at what is going on.
Ian.

 

[Rustking]

Thought you had 80000km of happy motoring since doing the egr delete......why are you doubting that mod now? Unless a resistor or diode has failed or the wiring connectors have failed, you should not be getting an issue there. 14.75 is too high but your multimeter may not be reading correctly. Try a different one. Should be max 14V. Your problem does not sound like a maf issue - it sounds more like an egr problem so you do need to check the above. The egr is supposed to open at idle after a preset interval before modification. Think you need to get a good indi to have a look at what is going on.
Ian.

Thanks for replying!

Actually I was thinking the same, 80000km and then suddenly failing. No, my thoughts were that the old MAF that failed, somehow should have fried the resistors. Reading a bit about resistors, this is not likely to happen, but I feel like I have eliminated that possibility now!

As i was about to order a new voltage regulator, I noticed that there are 2 versions, 14.2V and 14.7V. Assuming the last one is the proper one for my car, I cancelled that.

So, maybe returning the MAF, and asking for another? Downside is 2 weeks delivery, as I order from Germany to get a decent price.

The intake and egr valve is absolutely clean! Of course there is oil in there from the head vent, but no soot and no carbon buildup! Valve has clearly not been open for a long time.

So I think a spend my money on another MAF and a Fluke multimeter!

It's a bit frustrating, but eventually there's always a solution. I will report back when I get this right!

Off topic: I got the evox-r v2 projectors and a new set of osram d2s nbu in the mail last week, so I'm very much looking forward to start that project! I think I make a tread on that, as I feel people in here will appreciate that.

 

[zyggy]

In general it's felt that having the EGR (exhaust gas recirculation) system on diesel engines is good for reducing the NOX output but bad in all other respects.
It reduces economy, creates more smoke, increases problems and maintenance requirements due to clogging the intake and can reduce overall engine life.
As a result of wanting greater economy I decided to stop the exhaust gas being recirculated. The problem with doing this on a modern engine is that the EGR valve operation is monitored by the MAF sensor.
The only way to disable the EGR and not trip a fault code and limp home mode is to fool the MAF into thinking the EGR is still working.

On another forum I saw a member Karteck was also looking into this and performing some testing on what resistance values to use to create the required drop in MAF output when the MAF should be operating. He provided the below circuit to use.

The basic circuit for this comprises of two resistors to act as a potential divider and a diode to stop 12v being fed into the MAF circuit.

By connecting into the EGR vacuum transducer activation wire this causes the circuit to only operate when the transducer should be operating the EGR valve.

The standard circuit is a 1k ohm resistor, a 470 ohm resistor and a diode. 1/4 Watt resistors work OK.

The above is for a W210 300TD but the same components should suffice for most applications, but the connections will need to be determined.

First locate the EGR vacuum transducer and disconnect the wiring plug. Using a meter check which wire is the 12v feed and which is the active low signal wire.

Next go to the MAF sensor and again using the meter source the signal wire, which should be Pin5.

For ease of connection trace these wires back to the engine ECU. The easiest way to do this is to disconnect the connector, remove the screw in the back of the connector and prise the connector apart to reveal the wires.
In practice removing the screw and operating the over centre catch will part the connector.

Build the circuit and insulate the components then after locating the appropriate connections (12v, EGR active low, MAF signal) strip the insulation from the wires and solder the mod in place, then make good the insulation.
You will need to disconnect the EGR transducer electrical connection, so ensure you tape it up to stop any water ingress.

The final installation will look something like this, although normally the wires are tucked away by the side of the loom.

The next diagram is for a ML270 just to show the connections. It's the same components, just different ECU connections.

W210 300TD is:

Switched 12v (sorry, can't remember which pin I used)
EGR signal = Pin 35
MAF signal = Pin 21

ML270 CDi:

12v = Pin 37, plug 3
EGR signal = Pin 60, plug 3
MAF signal = Pin 24, plug 4

I think the above will work for all Vacuum transducer type EGR valves, but the connections may vary.

if you try this mod please report back your connections.