Yeah True, ECUs need coding to work. I think a new ECU is a blank one. Then you need to use the MBUSAmagic powers and put the new firmware on it.

I don't have pics, but I do have the service DVD. I am still my self researching more about this problem. Funny thing is when I got this car 8 months ago, its been noting but problems. Its been frustrating the whole time. BUT when i fix it and it runs good for a couple months MAN ITS GREAT, the power the handling, the sound of the 2.3L. Also if anybody is having this problem, and your not absolutely mechanically inclined, please don't try what I saying. ONLY if you feel comparable doing it. So I will be starting to work on my car, and taking some pictures along the way. I will post up some stuff when I get it. Attached is a picture from the service DVD. The picture is an older M111 non-supercharged engine. Component placement is still valid. Orange circle is magnet, and yellow circle is engine ECU. Hope it helps for now, and please help me out too. I love my car, and I don't want to buy a Prius, or Civic.

Rommel

 

Thats a M271 motor, and your going to drive a prius, thats sad! And the ECU is mounted to the side of the aircleaner housing, not where the front SAM is located.

 

Prius and Civic are a joke. And the ECU for the engine is mounted right next to the Front SAM. Its in the same box as the front SAM for the C230K coupe. I didn't say that the picture is exactly what I am talking about. Its only for reference. The picture is the only picture I have the engine bay.

 

The preventative solution on this is to put some silicone in the harness to prevent anything from flowing down through.

Used to do this on late model Bertone X19's on the FI computer harness as at times water would flow into the harness from the engine compartment into the
the FI computer, fry and kill the car, new computer required, and used to cost $600, though you can source them on ebay for about $35.
(E, you reading this?)

Anyway, as such, I still do not where to be putting the sillycone, or where the
point of origin of the oil mess issue we're discussing here as it relates to
M111. (E, can you point in the correct location?)

 

The oil leak seems to originate from the magnetic cam adjuster. It leaks where the connector connects to, and then the pressurized oil leaks through it and into the wire harness making a mess of everything. Just to let you guys know, I have installed the new updated until and that one failed also. I have removed the harness already, and the oil spreads all of it. Also found loads of oil in the intake track, and all over the MAF.

Rommel

 

That would work well but the oil flows inside the core of the plastic coating.

 

You mean through the insulation of the individual wires? (that would be bad)
Or the shrink wrapping that covers the harness?
If it's the latter, than you can fill the space with sillycone.

Still don't know where we're talking about on the M111.

 

The location of all this talk is the M111 main enigine wire harness that spans all over the engine. It terminates into the ME-ECU unit. Yes that is true that the oil runs through the harness through the core where the acuall copper lives. It also runs up through the insulation, and the sheathing, and anything else it finds. I heard from a shop that removing the wireharness, cleaning it very good buy disasembling the bundle and spraying it with eletrical cleaner would clean it very well but the oil in the copper strands will still remain.

I think as long as you clean the harnes very well, replace the cam adjuster, install the extra wire harnes between the cam adjuster and main wire harnes, and cleaning the ECU very well you should be in good shape. Well thats my plan. I hope it works. I dont want to buy a new harnes, ECU.

I also appoligize for my previos thread post about the picture being a M271 motor not an older M111. MY BAD!!

()()()()()()(QUOTE)
Thats a M271 motor, and your going to drive a prius, thats sad! And the ECU is mounted to the side of the aircleaner housing, not where the front SAM is located.
Quote:
Originally Posted by C230Krarana
Yeah True, ECUs need coding to work. I think a new ECU is a blank one. Then you need to use the MBUSAmagic powers and put the new firmware on it.

I don't have pics, but I do have the service DVD. I am still my self researching more about this problem. Funny thing is when I got this car 8 months ago, its been noting but problems. Its been frustrating the whole time. BUT when i fix it and it runs good for a couple months MAN ITS GREAT, the power the handling, the sound of the 2.3L. Also if anybody is having this problem, and your not absolutely mechanically inclined, please don't try what I saying. ONLY if you feel comparable doing it. So I will be starting to work on my car, and taking some pictures along the way. I will post up some stuff when I get it. Attached is a picture from the service DVD. The picture is an older M111 non-supercharged engine. Component placement is still valid. Orange circle is magnet, and yellow circle is engine ECU. Hope it helps for now, and please help me out too. I love my car, and I don't want to buy a Prius, or Civic.
()()()()()()(QUOTE)


Rommel

 

I'm sorry I ignored you post, yeah that O2, and I had a code like too also. What happened it the oil got to it and it didn't make a contact. Car run for about 2 weeks like that. I cleaned up the contacts and found that light went away, but then returned with another code for the heated element. I guess when the car was running for a week or so like that (my fault) to o2's heater element went bad for running too rich. I got 19 miles to the gallon when the O2's were not working. Got 2 new O2 and never had the code again after cleaning the sockets of oil.

Rommel

 

I have now seen this problem on a M271, so M111 owners you're not alone.

My service department says this problem has happened to a few cars now.

 

yes my service department in Walnut creek CA said that also.

Like in the privious post with the plan, I did remove the harness and cleaned it with eletrical cleaner. replaced the cam solinoid for the third time under parts warrenty, and also purchased the adaptor in the TSB for oil in wire harness.

After I had cleaned everything and replaced some parts, I have been lucky that it does not leak oil in the harness anymore, and everything works like a charm.

So sum it up, spend about 200 bucks in minimal parts and fix the problem in the TSB instead of spending $4500 in parts and labor. Thats a good deal.

Rommel

 

That's exactly what I am going to try to do.

The isolation cable looks good, installed it this afternoon. I'm confident it'll fix the leak into the harness.
NOTE: if your dealer says this will not fit your engine, they are wrong. It fit mine perfectly and I have the 271.740 engine not the 271.747 in the TSB.

Everything on my car is working fine, minus the O2 sensors. Going to clean all the connectors and hope the oil in the harness slowly makes it way out the bottom where the O2 sensors are.

NOTE: oil doesn't destroy connectors or PCBs, it merely causes a low resistance short or a bad connection. The reason the dealership wants to replace everything is cause they don't want to spend the time the time to clean it. Its easier to just replace.

 

To anyone interested.

I also completed the $200 fix, just replacing the cam sensors and buying the isolation cable in the TSB. I sprayed all the connectors with contact cleaner and cleaned as much oil out of the system as possible.

Car runs much better, will inspect in a few months as the oil continues to work itself out of the wire harness.

 

Unbelievable. I get a new job, go away from the forums for a few months, come here to find info on my bad O2 sensor code, and find this thread...

I pulled the connector off the cam sensor: oil soaked
I pulled the connectors off the ECU: little bit of oil

I didn't have a chance to see if it made its way down to the O2 sensor.

I'm really discouraged. I love this car. It's been rock solid for 97,000 miles and hasn't needed service since the warranty ran out. *But* I'm actually thinking of trading this thing in. I'll have two kids when October comes around. The car needs new snow tires, the paint is tired, 2nd gear grinds in cold, and now has an oil soaked engine harness...

 

avlis,

Oh no!! dont toss the car away, well ok fine, just get the new C300 and start posting on the W204 threads.

I just want to report on the the $200 fix that laster year I did the work and still today 4/27/2008 the fix still stands as fixed. I check the plugs for the ECU once a month every time i check the oil. I always do find that it still sweats because the residual oil in the copper but has never fouled the connector plugs and cause an enigine light to go on.

For thoses of you still needing to do this and just catching the thread at the bottem of this post please scroll up and read. THIS FIX WORKS!! but depends on how long it has been leaking.

Edit: Anybody who has done this please report if any problems after. Thanks.

Rommel

 

Tires are inavoidable. At least you won't need snow tires till next year.
2nd gear grinding? Just replace the tranny oil.
Do the diff while you're at it.

It's spring, perfect time to pull the harness and clean it.

These things happen on all types of cars.
It's just that with ours, the mechanics always propose the most expensive solution.
I wondered from the beginning, couldn't someone just soak the harness and clean it?
I'd think some sort of solvent would be the way to go.
It might take a Sat. afternoon, but it can be done.
Mercedes are still held together with screws and bolts, and they're not made of gold.

 

I wouldn't consider trading the car just for tires and this oil problem alone. My family is growing in Oct. and I could use 2 more doors for getting kids in/out. I'm coming up on 100k miles; stuff is eventually going to need replacing and I'm not sure I want the hassle.

I changed the tranny oil last year and 2nd gear was almost unattainable this winter. I'd like to get it rebuilt if I kept the car.

My dealer should have all the "$200 fix" parts for me this week.

This all started with an error code for the 2nd O2 sensor. What's the best place to get a new one? Dealer wanted $240-$260.

 

I did some searching today and noticed a post from 2005 that describes this leaking cam sensor problems. Too bad it was basically glossed over at the time, it would've saved a lot of us here some time and/or hassle.

 

I ordered mine here for $110 with free ON shipping.
(The upstream one) It's the exact one the dealer sell from Bosch.
People have commented NOT to buy the universal ones.
Those are listed a little cheaper.
http://www.autopartsworld.com/

rockauto.com is ok too.

As far as what will need replacing it's just a matter of whether you've stayed up on the maint.

Do you have the service sheet? PM me with an email address if you don't.
They have them for each year on the Service DVD.

 

how are they gonna clean the oil in the ECU? anyone know ??
I got CEL on and took the car in and my SA told me that i need to replace the engine wiring harness, downstream O2 sensor, camshaft solenoid adjusters, and adaptor cable.. > <
anyone know how many hours of labour this will cost ? my SA told me that its gonna be at least 5 hrs of labour..

 

Funny story.

Around spring time this year I got the partial load vent hose recall fix done. A couple weeks later my car started shaking again, CEL came on, and I thought it was the same problem. But nope, one of the top hoses was not clamped (dealers fault) and it came off. I put it back on and had it secured, car ran fine, but the CEL stayed on.

Ok sooo months go by, CEL is still on, car is running fine. I changed the Cam sensors and added the isolating wires. I drive to FL and get about 27-30 true mpg. I drive back and get about the same mileage.

CEL still on. November comes around. I've had my car for a year. Car inspection is due in November, and it can't be inspected here in NY with a CEL.

What to do? Mechanic I know erases the codes for free! Saves me $100. Gives an 02 Sensor (upstream) code. The CEL stays off, I drive quite a bit, and finally a few weeks later get it inspected.

And LOL! The very next day the CEL comes on while driving.

My car is barely getting 20 - 21 mpg highway, and I drive quite a bit on the highway.

I need to change the 02 sensor asap. I'm at 70k now.

I wonder if I should replace my engine wire harness as well...

 

It's an expensive replacement. To clean it properly you really need to use a solvent like Hexane. The trouble is that Hexane is nasty stuff - If you go this route - ON NO ACCOUNT INHALE AN EXCESSIVE AMOUNT OF THE FUMES & WORK IN A WELL VENTILATED AREA - excessive Hexane inhalation can lead to numbness & temporary paralysis of arms & legs.

It's a constituent of gasoline, glues etc.

 

$400 back in 2006? Dealer pricing? I may just replace it with a new harness.

 

My C230 has the EXACT same issue. Oil ruined the harness and the car has charging issue

 

This looks to be a serious defect with these vehicles, this is just a small sample of the problem I am sure. I am thinking a class action lawsuit!

I never heard of a car that has to replace wiring because oil can get into it!