W164 ML 320CDi Wastegate Solenoid
Discussion
Got a code on my ML relating to operation of the wastegate solenoid and was wondering if anyone knows whether this is the solenoid
It has the purple mark on it and is on the exhaust side of the turbo. If it is do you know what spanner size this is I am thinking somewhere in the low 20s. If anyone knows the part number that would be great as well.
It has the purple mark on it and is on the exhaust side of the turbo. If it is do you know what spanner size this is I am thinking somewhere in the low 20s. If anyone knows the part number that would be great as well.
mbtech01 said:
The item in the picture your referring to with the purple spot is an exhaust back pressure sensor. They are prone to blocking up & then putting the vehicle into limp mode & causing the vehicle to surge badly when try to accelerate. Its easy enough to change & is either 22mm or 24mm spanner size. you'd need to quote your chassis number to get the correct part number for the sensor as there may be a few options dependant upon your exact vehicle as this engine is fitted in several cars throughout the model range.
Thanks for that. Could it cause a P0244 code which relates to a solenoid? I have checked several sources and cannot find a solenoid for this turbo.Old post but thought I would update.
I had driven around the issue for a quite some time and finally took the turbo off the car and cleaned it with a product specifically designed for cleaning the vane mechanism. I did not take the turbo apart at that time and putting it all back together the car improved greatly but could still slip into limp mode if you pulled away with a few revs more than it liked.
So took it off again having found a turbo specialist not to far away and took it to him. He took the exhaust housing off and cleaned the surface where the vane mechanism sits. It had become pitted and collected carbon crud from the exhaust causing the vanes to bind a bit. He was going to fit a new vane mechanism but said mine was fine and it would be a waste of money. He also checked the actuator and that was working fine.
http://www.qualityturbos.co.uk/
Put it all back together and so far a complete fix. The car is no restored to its former glory with no more limp.
The car had done 46k miles and the turbo showed no signs of wear or issue and indeed at speed it pulled fine you just couldn't give it 100%. Total cost of fix was £72 for the turbo clean up and £200 for various gaskets, bolts, cleaner etc. So a lot cheaper than a recon and a hell of a lot cheaper than a new turbo.
I had driven around the issue for a quite some time and finally took the turbo off the car and cleaned it with a product specifically designed for cleaning the vane mechanism. I did not take the turbo apart at that time and putting it all back together the car improved greatly but could still slip into limp mode if you pulled away with a few revs more than it liked.
So took it off again having found a turbo specialist not to far away and took it to him. He took the exhaust housing off and cleaned the surface where the vane mechanism sits. It had become pitted and collected carbon crud from the exhaust causing the vanes to bind a bit. He was going to fit a new vane mechanism but said mine was fine and it would be a waste of money. He also checked the actuator and that was working fine.
http://www.qualityturbos.co.uk/
Put it all back together and so far a complete fix. The car is no restored to its former glory with no more limp.
The car had done 46k miles and the turbo showed no signs of wear or issue and indeed at speed it pulled fine you just couldn't give it 100%. Total cost of fix was £72 for the turbo clean up and £200 for various gaskets, bolts, cleaner etc. So a lot cheaper than a recon and a hell of a lot cheaper than a new turbo.
The turbo is time consuming to remove. The main issue is the fact it is at the back of the engine so the manifold bolts are out of sight. It would be a good idea to get hold of some small socket wrenches
http://www.ebay.co.uk/itm/3pc-Thumbwheel-Palm-Ratc...
an
http://www.ebay.co.uk/itm/1-4-3-8-1-2-Drive-Stubby...
and a pad as I found that kneeling on the slam panel allowed me to see better what I was doing. The gaskets are fairly straight forward but pay attention with the main exhaust connection which is a foil covered ring as I found it a little awkward to get the correct seal which is achieved by a clamp.
I can say that more than a year on I have had no issues and it is most likely that the internal vane mechanism is sooted up and sticking. You can remove the actuator very easily and have that tested to confirm it is not that. When I removed mine operating the linkage on the turbo by hand I could feel the binding of the mechanism and the actuator is designed to give an error if that binding goes outside of its tolerance.
http://www.ebay.co.uk/itm/3pc-Thumbwheel-Palm-Ratc...
an
http://www.ebay.co.uk/itm/1-4-3-8-1-2-Drive-Stubby...
and a pad as I found that kneeling on the slam panel allowed me to see better what I was doing. The gaskets are fairly straight forward but pay attention with the main exhaust connection which is a foil covered ring as I found it a little awkward to get the correct seal which is achieved by a clamp.
I can say that more than a year on I have had no issues and it is most likely that the internal vane mechanism is sooted up and sticking. You can remove the actuator very easily and have that tested to confirm it is not that. When I removed mine operating the linkage on the turbo by hand I could feel the binding of the mechanism and the actuator is designed to give an error if that binding goes outside of its tolerance.
ste68blue said:
Hi Slacker, thanks for the reply.
At the weekend i replaced my glow plugs and had to remove the actuator to get to the glow plug at the back, my question here i guess is what should the connecting rod feel like, once mine was detached from the actuator it was very loose or sloppy....is that how its supposed to be?
Cheers
Stephen
Well mine was not stuck but had a definite binding part way through the travel. Did you pull the linkage through its full range of motion (on the turbo not the actuator)? Have you checked for codes?At the weekend i replaced my glow plugs and had to remove the actuator to get to the glow plug at the back, my question here i guess is what should the connecting rod feel like, once mine was detached from the actuator it was very loose or sloppy....is that how its supposed to be?
Cheers
Stephen
The actuator can be tested, the guy I took mine to had a diagnostic machine which tested my actuator through its whole range of movement and it came through fine. Do you have a turbo place nearby where you could take the actuator? If so it could be worth your while to test it to rule it in or out. If the actuator is the cause then get a new/refurb one and problem is solved with a lot less work than a turbo removal/refit.
WOW! That is bad. These rings can allow condensed oil to drip down into the V and contaminate the flap mechanism. I have changed my seal in the past and also the oil breather seal to the left of the turbo into the plastic manifold in your picture. This could have caused an air leak which may well have caused your limp mode.
Edited by SLacKer on Friday 2nd October 14:21
Just google
mercedes om642 port valve shutoff
and have a read round the results. I wouldn't assume it is this that is causing your issue. You are replacing the seal, which is a CRAP design.
Drive the car and check you are not getting oil leakage below the turbo. I checked mine with an endoscopic camera and was happy I hadn't got a problem. The mechanism and electronics are buried in the V of the engine so are not immediately accessible for visual checking.
If the problem comes back get the codes. Nothing fancy required for engine codes even on a Mercedes. I use one of these (they have the code descriptions built in rather than some booklet). There are loads of others and various dongles and android phone apps.
Don't assume it is the port valves and worry yourself to death, get the seal replacement and fit it carefully and don't over tighten the clip. Then drive it and if it doesn't trip into limp mode then that issue is sorted.
mercedes om642 port valve shutoff
and have a read round the results. I wouldn't assume it is this that is causing your issue. You are replacing the seal, which is a CRAP design.
Drive the car and check you are not getting oil leakage below the turbo. I checked mine with an endoscopic camera and was happy I hadn't got a problem. The mechanism and electronics are buried in the V of the engine so are not immediately accessible for visual checking.
If the problem comes back get the codes. Nothing fancy required for engine codes even on a Mercedes. I use one of these (they have the code descriptions built in rather than some booklet). There are loads of others and various dongles and android phone apps.
Don't assume it is the port valves and worry yourself to death, get the seal replacement and fit it carefully and don't over tighten the clip. Then drive it and if it doesn't trip into limp mode then that issue is sorted.
TOYOKA said:
Got a code on my ML relating to operation of the wastegate solenoid and was wondering if anyone knows whether this is the solenoid
It has the purple mark on it and is on the exhaust side of the turbo. If it is do you know what spanner size this is I am thinking somewhere in the low 20s. If anyone knows the part number that would be great as well.
No the other sideIt has the purple mark on it and is on the exhaust side of the turbo. If it is do you know what spanner size this is I am thinking somewhere in the low 20s. If anyone knows the part number that would be great as well.
With the blue mark on it to the left of the turbo
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