C270 CDI EGR clean & test

[ccp]

Been getting a fair amount of smoke from my C270 CDI when accelerating hard and I've noticed that the boot & bumper is almost permanently covered in fine black soot so I thought I would inspect and clean my EGR valve as a starting point - particulalrly as its never been done and the car has done 96k miles

So I've stripped it down and am cleaning the black gunk away and now I want to test / see the EGR valve's operation before I put it back on the car. I'm pretty sure it works on vacuum? so I connected up a 20ml syringe and pulled the plunger out - nothing happened.

Has anyone else tried this and seen any movement, or is my syringe not big enough?

Has anyone else managed to test / observe the EGR working whilst its off the car?

Thanks

Charlie

 

[ccp]

bump

 

[Dieselman]

Just suck on the tube.
If the valve wasn't working the ECU would have thrown limp home mode.

 

[ccp]

Thanks DieselMan, despite sucking as hard as I could, the valve wouldn't move. I gave it a firm prod with a screwdriver and it did move so its not stuck - no signs of limp home mode either so it must be working.

It doesn't seal 100%, when I put some cleaner down the exhaust port there was a little weep around where the valve seats, but I would guess this is normal given the construction and its application.

I've put it all back together now and it runs olk - I'll see if its made any difference to the amount of smoke when it kicks down.

 

[Buffers]

You could be getting smoke on kick down if your intake manifold flaps are worn or not functioning correctly. Had the same problem with my C270cdi and removed the flaps from my manifold altogether, no smoke now and seem to be getting more mpg.

 

[ccp]

Thanks Buffers. I suspect that the manifold flaps will be my next move - I could see black oily deposits all over the flap mechanism for no. 1 cylinder whilst I had the EGR valve off.

 

[Buffers]

Keep us informed how you get on!!

 

[Geoff A]

You could be getting smoke on kick down if your intake manifold flaps are worn or not functioning correctly. Had the same problem with my C270cdi and removed the flaps from my manifold altogether, no smoke now and seem to be getting more mpg.

Tell me more about these flaps please, being a C270CDi owner ('05) I'm curious. What's the idea behind them and is there an advantage for keeping them or removing them?
They sound like a restriction and I guess they would be if stuck shut.

 

[stipple]

me too

Hey guys im new to this but giving it a go i too have the same problem with my C270 CDI... its got such little power and quite smokey.. ive changed the MAF sensor, had all the injectors checked and even had a recon egr valve fitted but none of this has worked.

Im told about the inlet manifold flaps and was advised to just remove them completley

does anyone have any information at all on this subject please

 

[Buffers]

Inlet port shut off motor delete (CDI2) - Mercedes-Benz Owners' Forums

I am not great at adding links but l have pasted this from the browser bar. Might help.
Still pleased l removed the flaps from my W270cdi, no smoke and more mpg.

 

[Buffers]

Inlet port shut off motor delete (CDI2) - Mercedes-Benz Owners' Forums

I am not great at adding links but l have pasted this from the browser bar. Might help.
Still pleased l removed the flaps from my W270cdi, no smoke and more mpg.

 

[Jane270ML]

For the new guys... here it is... http://www.mbclub.co.uk/forums/engine/105515-ml-w163-270-egr-pipes-manifold-cleaning.html

Do a search in the forum for many more details.

 

[stipple]

Thanks

Thanks guys ill check it out! in the mean time if anyone has any more info would be very grateful!

 

[Buffers]

http://www.mbclub.co.uk/forums/engine/132206-inlet-port-shut-off-motor-delete.html