CRJ

Last weekend I did an oil change on my wife's 2003 c230. When I was done I took it out for a drive and had no issues. The next day she went to take it to work and as she was driving(not far from home) it started sputtering and idling really hard. I looked at when I got home and found that Cyl 2 & 4 were misfire and the camshaft postion sensor was in open.
I changed the plugs( but not the coils or wires), cleared the codes. Same thing. Poor thing sounds like it is dying a harsh death. Checked the codes again, Cam sensor back on. Replaced sensor. Same thing. This time no codes at all.
So upon further reading I checked the $12 hose. It looks new and is in good condition. But during the process of diassembling everything I found that there was oil in the MAF sensor harness, fuel injector harnesses, and a little in the ECU harness. There is also a lot of oil on the throttle body hose. I cleaned all with their appropiate cleaners, reassembled and
put in a new air filter.
Next I put in a new fuel filter. No difficulties there but the gas didn't smell like gas and there was a large amount of black deposits mixed in with the so called gas in the filter. I went and got Sea Foam to hopefully stabilize the gas and put the key in.......
WTF!! Now I have codes 300(random misfire),
301,302,303,304,(misfire 1-4)325(knock sensor),
and 0010(camshaft sensor at intake)
Help me

phister

have you checked out this thread

https://mbworld.org/forums/c-class-w...nsor-leak.html

LILBENZ230

The oil in the harness is one issue and the other possibility for the 2003 car is the head issue which is a big expense. Let us know what you find out.

CRJ

OK apparently i replaced the wrong sensor. A guy on another forum told me it was the on that is next to the coils on top of the engine. Obviously this is wrong. I read the link that was on the second post. I will order correct one today. I'm not to happy. So my next question is does the actuator throw all the codes that I have listed or are we still talking head issue. My HG went on my LR Disco and replaced that myself and didn't see any of the problems that I'm having here.

CRJ

Just check harness at camshaft actuator intake. No oil. Appears was fixed once because there are isolation wires on them already. Did find traces of fluid around where the coolant hose connects. How did the oil make it into the all the other harnesses ? Do camshaft actuators just go?

CRJ

Put new camshaft magnet in and it is still rough and still is giving me the code for the actuator i just replaced. I pulled off the the harness on the exhaust side and it has oil in it along with oil in the harness of the postion sensor exhaust side. I also looked at he spark plugs that I just replaced and there is oil on the threads of all four. Pug seals are good, no oil in plug tube. Looking into the combustion chamber from plug hole it appears that the heads are all black. Rings? I'm going to run a compression test. Do bad rings account for oil in all the harnesses?

Glyn M Ruck

Rings have nothing to do with oil in harnesses. Oil in harnesses comes from leaking cam sensors on the front of the engine that need to be replaced & pigtales fitted. See thread above.

If you can't clean the harness you will have to replace it. Oil in plug threads is nothing to worry about. You might have coil problems as well on misfiring cylinders.

Glyn M Ruck

If the above is not the issue you need to find someone with a boroscope to inspect the inlet valves for fouling that used to occur on pre redesigned heads in poor fuel areas like the US.

CRJ

Ok, now lets review. First misfire and misfire codes along with camshaft magnet intake (CSM). Replaced CSM. Same problem, same codes. Cleaned MAF, new coils, new plugs. Same problem only CSM code. Looking into combustion chamber with flashlight, the heads are black with crap. Oil in injector harnesses, pulled injectors and they look to be oily on tips. Possible? Pulled valve cover to check gasket out of curiosity I checked timing chain. Pulled lightly to check tension, was tight at start of pull then chain slipped down into crank by two or three holes and now has slack. Guide rails appear fine. Tension Bolt? Talk of inlet valves. Do any of the problems above happen pairs to make one problem. All of it seems so random. Thanks for all your help in advance.

LILBENZ230

It sounds like your car has the head issue the 2003s were notorious for.