E350 3.0 bluetec OM642 No power/No fault.

Page may contain affiliate links. Please see terms for details.


Active Member
Jul 28, 2023
North Yorkshire UK
E350 3.0 v6

I thought I post my recent experience with my "baby" :)
Beginning of July I've noticed oil on the driveway. Took it to local garage (cowboys) and hot diagnosed with crankshaft seal, but got told that they can do it in 4 weeks. So I used the car and kept checking oil level. Got back to them and few hours later phone call saying that now oil also comes out from the front of the engine and they working on it to diagnose what happened.
Week later no solution and they informed me that they got a local Merc expert to diagnose my car. Unfortunately,he also failed,but as he had contacts...took pictures and sent it to Germany and we were waiting for reply. Just wondering who is going to pay for...lets say lack of knowledge. Another couple weeks and nothing back. Lost my pension and went back to see the "A team". Asked if they checked oil cooler seals, and got told that it was checked and is definitely not that. Fortunately, I bit stubborn and organised endoscop put it all way down into "V" only to find out massive leak. Needed car back as quickly as possible, but they said it be at least 1 week. This pis.. me of and decided to do it myself. With great success, seals replaced in approx 20hr. Which would make me poorer by £1000. No more leaks and car ran as before.
400miles later on motorway, car decided to shake like mad and started to slow down. Got of the motorway switched engine off ,back on. Sounded fine. Slowly set off, but when put foot on accelerator it just wouldn't go. Limp mode, or something like that. No EML, no faults. Weeks of scratching my head. One garage (must be turbo), second (Nox sensors), third (boost pressure sensor)....good job I am stubborn and if I don't believe in something nobody will change my mind. Hahaha. Yesterday took car home, still in limp mode but couldn't be bothered with this idiots. When got home, straight away smell of diesel and small diesel poodle. Looked under the bonnet and found diesel return pipe/connection on cylinder 6 leaking like mad, only because I haven't pushed it in properly. I thought brilliant at least one thing sorted. But still thought that no boost issue needs something out. Only to get into today car as Mrs done my head in, engine on...set of slowly as this I thought was only way to drive. Accidentally pressed accelerator hard.....and my baby went flighting. I couldn't believe. Done some reading and it's important that return line is pressurised, obviously with one connector of it wasn't.


As most know oil cooler seals are common issue. There is one drain hole which allows oil to drip into bell housing and back down. However there is, another hole at the front of "V" I think in case back one got blocked. So don't panic if you see oil at the front and back. Hopefully it the cooler seals.

Don't think crankshaft seal is common compared to seal but put pressure on you mechanics to use endoscope to verify it.

If there is no faults,it's likely something simple but not necessarily obvious.

Hope this post help you one day.


  • Weep Holes.jpg
    Weep Holes.jpg
    258.8 KB · Views: 9
I hope you cleaned out manifolds while you had access, I also sorted swirl flap linkages which were badly worn. After the work got more mpg and car drove like new 😉
I hope you cleaned out manifolds while you had access, I also sorted swirl flap linkages which were badly worn. After the work got more mpg and car drove like new 😉
I've cleaned as much as I could. But seeing pictures on various websites ,mine wasn't looking anywhere near. Touch wood....if I had to do it again, I would definitely done things different. Just like you said..."while you there". So far so good 👍

Users who are viewing this thread

Top Bottom