W210 E320CDI Turbo issue

[twitch]

Hey folks

Seem to have an issue with the turbo failing on my 2002 E320CDI estate.

Had star machine on, not showing any codes so its down to trial and error to see what the fault could be.

Start the car, drive off, turbo is working but only up to about 2500/3000RPM and theres then a kind of screech/whoosh and it wont go past that unless I ease off the accelerator, after about a mile or so, the turbo wont work at all and the car will easily rev and drive past the 3000rpm mark all the way to the red line. It will sit at 80 on the motorway all day when it eventually gets there so I dont think this is limp mode?

This makes the car really slow especially if needing to overtake on the motorway.

Switch the car off then start it back up and the turbo works as above again for the same amount of time.

Had a new MAS sensor a few months ago, no difference.

No oil leaks.

What would you look at to try and solve this problem thats bugging the hell out of me now, fuel consumption is rubbish too at the moment.

My regular non merc teccy has mentioned maybe the EGR valve clogged and/or the wastegate valve is jammed. Also mention of vacuum pipes but not sure which ones they are on the car.

Its just passed a MOT somehow too so I'm happy to run it into the ground!!!

Dont wanna chuck a load of money at it, if anyone has any suggestions, youtube vids etc or other very handy DIY jobs to check or look for I'm prepared to give it ago to see if I can fix it.

Thanks in advance

 

[Richard1973]

Looking at removing and cleaning/ replacing the egr valve on my 320cdi too as mine has a smoke issue under load. Anyone tell me how big of a job it is and what parts, gaskets,seals etc I need? Also, what's going to break in the process? Already had the brittle fuel pipes issue doing the thermostat!

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[bob6600]

EGR removal is not too difficult. It does bolt to the intake manifold and has a securing bolt underneath which I found easier to remove from the other end - it connects to a bracket which bolts to the engine block.

Well worth doing if it hasn't been done, a sticky or clogged EGR can be troublesome.

@OP

Did you change the MAF for a genuine one? Does the turbo actuator move when revving the engine? Does the flap motor on the intake move when revved?

I am surprised STAr showed nothing, it would/should log faults like this

 

[a111r]

EGR removal is not too difficult. It does bolt to the intake manifold and has a securing bolt underneath which I found easier to remove from the other end - it connects to a bracket which bolts to the engine block.

Well worth doing if it hasn't been done, a sticky or clogged EGR can be troublesome.

@OP

Did you change the MAF for a genuine one? Does the turbo actuator move when revving the engine? Does the flap motor on the intake move when revved?

I am surprised STAr showed nothing, it would/should log faults like this

Going to do mine. Running rough.

Having dismantled a breaker OM613 last year...
Would it be easier to remove the inter-cooler pipe below to liberate the EGR, rather than the water cooled exchanger that bolts to the rear of the cyl. head?

 

[Auto-mobile]

What diagnostic machine did you use?

Have you checked the turbo for play?

 

[bob6600]

Going to do mine. Running rough.

Having dismantled a breaker OM613 last year...
Would it be easier to remove the inter-cooler pipe below to liberate the EGR, rather than the water cooled exchanger that bolts to the rear of the cyl. head?

From what I remember, the exchanger needs to be unbolted with a loss of some water to get it off. I'm sure I tried leaving it in place but I could not get it back on without the cooler being slack and then tightening the two up slowly together. This 'pulled' the cooler into the EGR which could not do by pushing it.

 

[twitch]

EGR removal is not too difficult. It does bolt to the intake manifold and has a securing bolt underneath which I found easier to remove from the other end - it connects to a bracket which bolts to the engine block.

Well worth doing if it hasn't been done, a sticky or clogged EGR can be troublesome.

@OP

Did you change the MAF for a genuine one? Does the turbo actuator move when revving the engine? Does the flap motor on the intake move when revved?

I am surprised STAr showed nothing, it would/should log faults like this

Bob apologies if I come across a bit thick on this, no idea where the EGR valve is on my car but I'm sure I can find it and take it off and clean it.

Not sure on the turbo actuator, any pointers to where I should look? Same with flap motor too.

MAF is a genuine merc one.

Yes the STAR machine at my merc indie tech showed no faults for this as described in my OP.

Thanks

 

[bob6600]

Bob apologies if I come across a bit thick on this, no idea where the EGR valve is on my car but I'm sure I can find it and take it off and clean it.

This picture is taken from the RHS of the engine bay looking towards the left. The metal cooler is nearest yo you in the picture. Under the two pipes if the EGR valve which is attached to the mixing chamber with 3 torx screws, it all needs to come off.

Not sure on the turbo actuator, any pointers to where I should look? Same with flap motor too.

Standing infront of the car, the air box is on the left. Look under it and you can see the exhaust and turbo. The actuator is on the turbo.

Different engine but looks the same in the video

[YOUTUBE HD]yGIzTJPacf0[/YOUTUBE HD]


Finally. the flap motor is in this picture, just under the manifold

 

[a111r]

From what I remember, the exchanger needs to be unbolted with a loss of some water to get it off. I'm sure I tried leaving it in place but I could not get it back on without the cooler being slack and then tightening the two up slowly together. This 'pulled' the cooler into the EGR which could not do by pushing it.

Thanks Bob.
Yes it's somewhat odd, just a push fit joint between them, with what 'looks like' a large buna O ring as the seal ... against sub-EGTs.

Did you use a new seal on re-fitting?
I've since found my 2 salvaged parts in the cave and, as you said, they don't want to 're-unite' very easily.

With a new seal perhaps there is an easier 're-union' of the two parts?

 

[bob6600]

Thanks Bob.
Yes it's somewhat odd, just a push fit joint between them, with what 'looks like' a large buna O ring as the seal ... against sub-EGTs.

Did you use a new seal on re-fitting?
I've since found my 2 salvaged parts in the cave and, as you said, they don't want to 're-unite' very easily.

With a new seal perhaps there is an easier 're-union' of the two parts?

I have reassembled with the old seal and with a new one, makes no difference. It is a very tight fit and only tightening the bolts pulled it in properly.

If I bolted the cooler on first, the mixing chamber was way off line.

 

[Richard1973]

Had a look yesterday and it looks like the swirl flap linkage is missing from the motor. Is it possible the have been disconnected?

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[bob6600]

Yes, but cannot remember if there was a by-pass for this?

This could be your problem.

 

[a111r]

The linkage defaults to the open valve position. The link connectors are know for coming off.

My motor was faulty - cured by the 4.7K ohm resistor fix between the plug's connectors