Terrible MPG on Kompressor

[LostKiwi]

So you changw change the cable out and put the new harness in. What do you do if its got into the o2 sensor and stuff?

No it goes at the cam sensor end and fits inline with the existing harness. Simply unplug the existing connector, plug this in between the existing harness and the sensor.

 

[Trueblue1872]

No it goes at the cam sensor end and fits inline with the existing harness. Simply unplug the existing connector, plug this in between the existing harness and the sensor.

Ok gotcha. I think a little investment in these will help. Kiwi that Mercedes of Grangemouth dont gakf take tgeir time in answering you.

 

[LostKiwi]

Never had an issue with them to be honest but then I don't use them very often. Did you phone or email?

 

[Trueblue1872]

Yes iv emailed twice i will maybe give them a call.

 

[LostKiwi]

Phone always works best.

 

[Oldspanners]

So you changw change the cable out and put the new harness in. What do you do if its got into the o2 sensor and stuff?

The cable blockers are just a solid piece of wire that plug into the cam magnets and the wiring harness and prevent oil wicking up the braided wire in the harness. It depends on how long the oil has been wicking up the harness as the lowest point is the after cat O2 sensor connector beside the gear box but it may get as far as the ECU connector as well. You can clean it out as I said but it may take a while depending on how bad it is.

 

[Oldspanners]

Yes iv emailed twice i will maybe give them a call.

If the cam magnets are the problem this is what you'll need ;

OM271 Camshaft Magnet Wiring Harness A2711502733 2 off
OM271 Engine Camshaft Magnet Seal O-Ring A0109972348 2 off
OM271 Engine Camshaft Magnet Grommet A2710510032 2 off
OM271 Engine Camshaft Magnet A2710510177 2 off

I got mine from Mercedes in Newcastle and emailed my VIN to confirm the correct parts.
Edit put the same part no. in twice!

 

[Trueblue1872]

C

If the cam magnets are the problem this is what you'll need ;

OM271 Camshaft Magnet Wiring Harness A2711502733 2 off
OM271 Engine Camshaft Magnet Seal O-Ring A0109972348 2 off
OM271 Engine Camshaft Magnet Grommet A2710510032 2 off
OM271 Engine Camshaft Magnet A2710510177 2 off

I got mine from Mercedes in Newcastle and emailed my VIN to confirm the correct parts.
Edit put the same part no. in twice!

Cheers for that spanners i priced the cam magnets and they are abour £38 each. Just need to see if i can figure out wherw the blocks go.

 

[Oldspanners]

C

Cheers for that spanners i priced the cam magnets and they are abour £38 each. Just need to see if i can figure out wherw the blocks go.

Yes that's the price but surprisingly the blockers which are really only solid wires are about £25 each!!
You'll need the O rings and grommets as well.
The blockers simply plug into the cam magnets and the wiring harness plugs into the other end of them.
This video shows you how to change the magnets but has the blockers already fitted which he shows.

Edit to show Youtube video.

 

[Trueblue1872]

Ye i seen that video mate thats the one i watched earlier. Kiwi gave me a link to the wiring harness on ebay so getting there slowly but surely.

 

[ErnieC]

This is one of a number of threads that discuss the cam magnet oil leak and the consequences as the oil heads off around your wiring loom to cause poor connections at any number of connectors and generally mess up your engine so I will add my two cents here.
There are loads of these engines out there and its a question of when not if you are going to get caught by it. MB have invented the retrofit additional wiring loop to prevent the oil getting into the main loom but after years of main dealer servicing never has the fitting of these been recommended for the car I'm working on. That's shameful customer service in my view. They knew it could be an eventual costly problem -£2500 quoted in this case - wiring loom, ECU, sensors etc etc.
I've got O2 sensor error and this appears to be the favourite destination for the oil according to most threads. At the lowest point I guess this is natural what with gravity and all. I cleaned up the connector but I'm going to replace the sensor anyway. There's a larger, squarer wiring connector located immediately above the round post-cat O2 sensor connector and when I opened that one up I nearly got an eye full of 5W-30. Its true - always wear safety glasses.
There is a thread on MBWorld I think, where someone has fixed the cam magnet leak rather than replace the things at £loads each. I have followed suit and hacksawed off the three aluminium rivet heads which hold it together. The thin silicone washers inside are what have failed and let the oil past. I have added a suitable flexible gasket cement to each side of these and put the sandwich together again - my expectation is this repair makes it considerably better than the original device - I will update in the future when I'm proven wrong (or right). The O-ring behind the cam magnet needs replacing but I can't be doing with paying 6 or 7 quid for something that costs less than $2 stateside - why is it we are always being fleeced in the UK ? This too will get the gasket cement treatment.

 

[mercedes13156]

Won’t be timing chain
MAF sensor is definetely a check
Have you had the codes read?

What part of Scotland are you in? I'm near Edinburgh and have an iCarsoft scanner. Free to Forum members.

 

[John Laidlaw]

What part of Scotland are you in? I'm near Edinburgh and have an iCarsoft scanner. Free to Forum members.

Think you meant to reply to trueblue1872- I’m the truemaroon1874 type!

 

[Wighty]

No it goes at the cam sensor end and fits inline with the existing harness. Simply unplug the existing connector, plug this in between the existing harness and the sensor.

Just been reading this thread as another owner of an M271 engine , am I right that this modified harness would be worth fitting regardless of changing the camshaft magnets just to prevent this oil wicking occurring ?

 

[Wighty]

Just been out to the car and checked both magnet electrical connections , the left hand one did have a bit of oil in it , but I couldn't see any oil at the rear wire end of the electrical connections . I've sprayed both with electrical cleaner and I'll reconnect them later . I better get researching on this issue

 

[mercedes13156]

Think you meant to reply to trueblue1872- I’m the truemaroon1874 type!

I did. You're not a Jambo..... are you? We're all 1888 ers!

 

[Wighty]

Just ordered 2 of the blocker cables from MB Newcastle for £56 . Got them on express delivery for my Austria trip . I'll worry about checking for any other oil ingress when I get back from there .

 

[ErnieC]

Just ordered 2 of the blocker cables from MB Newcastle for £56 . Got them on express delivery for my Austria trip . I'll worry about checking for any other oil ingress when I get back from there .

I say you are a wise person. You might just have saved yourself a shed load of grief/money.

 

[LostKiwi]

Just ordered 2 of the blocker cables from MB Newcastle for £56 . Got them on express delivery for my Austria trip . I'll worry about checking for any other oil ingress when I get back from there .

Good plan. An ounce of prevention is worth more than a pound of cure.

 

[Craiglxviii]

Think you meant to reply to trueblue1872- I’m the truemaroon1874 type!

It’s a different language ah telt ye!