Technical guys,please help,missing and smoking w210 320 cdi

[turbopete]

sounds like the MAF sensor is bust. What if you disconnect the MAF and drive the car? Is it still exactly the same. You should be getting error codes? Are you certain it is the MAF and not Air Temp Sensor or something?

Don't really know about the throttle flaps, I think they should move, there are both swirl and charge inlet ports, can't say what the difference is.

swirl makes the air in the cylinder swirl to mix the air and fuel better and charge will be from the turbo boost. thats how i understand it anyhow

maf faults often dont bring up codes

 

[shaun 320cdi]

Hi kevin,i couldnt actualy see the balljoint,can just tell thats what it is!!it looks like a plastic poper on top of the balljoint,it looks all intact!!nothing adrift.

rich,its def the air mass meter,its on front of the airbox.

i didnt drive it,just tryed on the spot rev up to see if it made any difference,but didnt.

could it be the air mass meter??,although when we plugged it in,there was no error codes,if something was not working?,would it not show up as a fault??

do these mercs have a check engine light?or is it the glow plug light??

thank shaun

 

[Alex Crow]

shaun, you did not try it with the vacuum disconnected!! please repeat the above procedure but DO NOT RECONNECT THE VACUUM pipe until you HAVE tried it up and down the road. if it is jamming this test will only work if you leave the vacuum disconnected, as otherwise it will just jam open again as soon as you reconnect the vacuum!

the missing you heard when you hit with a hammer is lumps of carbon being dislodged - this is very common if a little unnerving, and also suggests that you have fairly heavy carbon deposits in the egr valve...

 

[Alex Crow]

yes there is a check engine light. as kevin correctly says the flaps should move when the throttle is 'blipped' at idle. if they are jammed the ecu will severely limit power production and revs. more likely the linkage has broken and the servo is actually moving fine, but not the flaps obviously.

 

[shaun 320cdi]

alex,you are a great help,i under stand that i should of driven it up the road,but the problem im having is a miss and white smoke holding the revs at between 2500-3000 rpm it wont realy rev through this it just knocks and missfires worse.

also there is also another little arm you can see through the top of inlet manifold,just under the fuel filter which moves when you blip it.whats this??

what does the check engine light look like as im not getting one when ignition on i dont think?

thank shaun

 

[rich.g.williams]

engine check light is yellow/orange shaped like a simply drawn engine. It should be coming on with all of what's happening, unless its only the MAF thats faulty

 

[Alex Crow]

hi shaun, the arm you describe sounds like the linkage to the flaps which kevin has kindly pictured for us.

the missfire you describe could possibly be one of the broken flaps bouncing around in the inlet port and jamming the valve - this does happen!! see kevin's picture for the flap also.

check engine light will be yellow, and possibly marked 'EPC'.

 

[shaun 320cdi]

this arm im on about is not near the arm for the flaps by the look of it.

has anyone got a pic of there check engine light on the same vehicle as im sure i havent got one!!the problems continue!!!

it looks like i bought a lemon,but i did buy it cheap through the trade,it was a part ex that had just come in!

im sure il get it sorted soon.

i wonder if kevin can blow that picture of the manifold with the servo on as i cant see it that clearly to see if its the same thing ive seen on the car?

thanks for now shaun

 

[Alex Crow]

shaun, i suppose you are now wondering if the bulb has been taken out - oh dear! the servo motor for the linkage has an arm that is where you describe, not directly inline with the flap linkage but nearer the n/s of the engine, you can see the servo from underneath in kevin's picture.

 

[shaun 320cdi]

hi alex,yes if can see a pic of the check engine light then i can see where its suppose to be and change the bulb!!! then carry on from there.

am i right in thinking,if i can see the arm moving then the rod linking the flaps should also move?

if i find the linkage has broken,should i be able move the flaps by hand??

thanks shaun

 

[shaun 320cdi]

and also noticed today,the head is missing off no1 glow plug!! it comes up as fault with no1 glow plug on scan,thats why,its not connected!!! apart from not starting in the cold properly,will this cause anymore problems?

 

[rich.g.williams]

Don't worry about the engine light just now. If its on the computer sees a fault, if its off the computer doesn't see a fault. Either way you have a fault so something is wrong.

A non working glow plug will make cold starting harder but after a fairly short time they go off anyway. Its not causing your main problem.

Don't worry sounds like you will get to the bottom of it.

 

[kebo57]

also there is also another little arm you can see through the top of inlet manifold,just under the fuel filter which moves when you blip it.whats this??
thank shaun

Hi you can see the flaps rail through all the gaps in the inlet manifold see arrow in pic if you see the rail move when you blip the throttle then the motor must be working might be able to get a mirror under there look for all the connections see if all the flaps are working. found another pic of the rail

Kevin

 

[shaun 320cdi]

ok.il get checking tommorow

thank shaun

 

[shaun 320cdi]

hi guys,ok next update, ive tryed what alex said with the egr again,and its no better.

i have tryed a new air mass sensor and still no difference.

i have had a good look at the throttle flaps.

the flaps all seem to be free,if you move the arm,they are seem to move freely,but i now cant see the servo moving when you blip the throttle!

when do these flaps open properly??is it under hard driving??

thanks shaun

 

[andy@pcd-ltd]

The only thing is you can see the flap arm moving but you cant actually see the if the flaps are moving unless you have taken the inlet manifold off.
I have had these before it seems ok from looking at the rod as it moves freely so doesnt log a fault wit the ecu but when you actually remove the manifold the flaps had broken off and was blocking the intake

 

[kebo57]

the flaps all seem to be free,if you move the arm,they are seem to move freely,but i now cant see the servo moving when you blip the throttle!

when do these flaps open properly??is it under hard driving??

thanks shaun

Hi the flaps rail shouldn't move freely as it is attached to the servo motor and that is difficult to move when the engine isn't running,

It will move but it will have a fair bit of resistance so you might damage something if you try and force it, you can get your right hand down the back of the inlet manifold and under it and feel the motor, blip the throttle with you left hand (on a ML 270 setup don’t know about your motor)
A quick blip about 1500 rpm should move the flaps, blips about every 2 seconds would show the flaps moving back and forth, but you wont know just what you are feeling under their it sound easy but, you could sort of help it to get started by assisting the start of its movement its easy for me as I know what is under there but yours could be a different layout

More about black smoke & flaps here http://forums.mercedesclub.org.uk/showthread.php?t=52840

Kevin

 

[shaun 320cdi]

HI kev,understand what your saying,i can only move the flap rod about 3-4mm,its just the play in the linkage,im not moving the servo etc.

ive got a mobile merc man coming to plug in tommorow,il see what he comes up with,if he has no luck,i think maybe the manifold off is the next job.

thanks again for all your help

shaun

 

[turbopete]

manifold off. hmm that seems familiar............. (not on a cdi though)

 

[shaun 320cdi]

doesnt look too much of a bad job?