Hello, here is the story. Car was running smooth until few days ago when I started the car, it started vibrating and check engine light came on. I plugged in my code reader and got 8 (!!!) codes.

Here are they, P0300 (random misfire), P0301 (cyl 1 misfire), P0302 (cyl 2 misfire), P0303 (cyl 3 misfire), P0343 and P0368 both "short circuit to positive or open circuit" on those two hall sensors. P0343 for B6/5 intake, and P0368 for B6/7 exhaust. And two other codes that I think are irrelevant but somehow connected to the problem P0108 pressure sensor (B28) high input, and P2015 for which I could not find adequate explanation.
I searched on here and found that misfires can be caused by those hall sensors (camshaft position sensors). So I went to the dealer and got 1 (just so you guys know they are all the same just place where you put them is different). Installed it, reset the codes and started the car again. It was running fine for like a minute maybe two, then all of a sudden it throws all those codes again. So I call this guy I know that works at Volvo dealer, I describe the problem and he said it is probably wiring and I should check for continuity/shorts. So I subscribed for the Startekinfo thing to get those wiring diagrams. Everything seems to check out, but one thing. On the coils there are 4 wires, according to the diagram pin #2 and #3 should not get continuity but I do get continuity. Either I am reading the diagram wrong or there is really something going on.
So look at the first pic. Circled are the coils (T1/1, T1/2, T1/3, R4s are spark plugs) as you can see wires #2 are all connected and go to the right (left physical side of engine where the coils of 4,5,6 cylinders are also connected with #2. The #3 wired are also connected and are grounded to the engine at the connection labeled W11w2. So if I understand it correctly #2 and #3 should not get continuity, but I get it on all coils.


Second wiring problem is with hall sensors. I get error that says “short circuit to positive or open circuit.” I looked at the diagrams again and getting continuity where I should, so there is no “open circuit” that rules out the possibility of short circuit. Can a faulty exhaust hall sensor make that code? Also if you look at the diagram it is connected to MAF sensor (B2/5) pin #1.




So there, that is about it. School starts in about a week, Aug 31, so I need to fix the car by them, would be extremely appreciated for any pointers/tips/hints. Thanks in advance.

 

Any reason you don't want the dealership to fix it?

 

cost, their mechanics will charge around $150/hour, plus parts. And I just spend like $400 for books.

 

I don't understand.

Did you mod your car and in doing so you caused the problem?

Do you have over 50K miles? From another country that Mercedes Benz does not offer a warranty? I'm lost.

 

Car is here in US just out of warranty, so all repairs will be at my expense

 

You put a fast 50K miles on your car!

I would keep away from the coils since they should be fine, if needed a quick way to test coils is to move them to a difference cly and see if the problem follows.

I think it's a sensor that has gone south, if you remove your battery cables and let the car sit for a minute I bet you'd get the same response from your car as adding that new sensor, it would run fine then kick into limp mode.

Have you checked the connections at the injectors? are you sure they're firing off in those problem clys?

My guess is a sensor has gone south, it's just a matter of finding what sensor =( With my turbo car, I have 4 O2 sensors and due to my exhaust setup, the O2 sensors tend to freak out from time to time, when it happens my car will throw all kinds of codes. I know its fine so I just ignore it, but it does cause the little OBD2 computer readers to think many random unrelated things are wrong.

So many things could be the cause of your problem. I wish you much lucky with finding it. Electrical problems suck.

 

Isn't that the truth.

 

Generic
P2015 = Intake Manifold Runner Position Sensor/Switch Circuit Range/Performance

MB specific
P2015 = check start control.Circuit open
P2015 = check start control.short to ground
P2015 = check start control.Short
P2015 = EGR system leaks (work link)(P0440)
P2015 = Purge control system has leak (function chain)(P0440)
P2015-001 = S40/3 (clutch pedal switch),trouble
P0343 = Camshaft Position Sensor Circuit High Input
P0368 = Camshaft Position Sensor "B" Circuit High Input (Bank 1)

OBDII protocol states that Bank 1 is the bank that contains cylinder 1 so this is consistent with your findings. This is a *****!!

If it is not a CPS (cam pos sensor) - I would mark & move coilpacks around to bank 2 to see if the misfires change cylinders as recommended above. This also takes wires out of the equation. Coilpacks & wires do fail on these engines. It would seem unlikely to be plugs - 6 plugs at once - I don't think so.

If you ignore the diagnostics - which do throw up BS at times - I'm surprised you have no CANBUS codes

It could also be the CPS - crank position sensor - cheap & easy to check and every owner of these cars should carry a spare - common failure.

Also try cancelling all codes. Unplug the MAF run the car & see if the codes reappear. This forces the ECU onto a default map which will tell you if you have a dirty or faulty MAF - I would however generally consider that MAF problems would effect both banks & your problem is confined to Bank 1 it would appear. That said you are not getting fuel trim codes & the MAF does try to average inputs from both banks primary O2 sensors via the ECU. Give it a bash - can do no harm.

Good luck - If the Cam position sensor is not the culprit - this one is not easy unless it's coilpacks or wires.

 

Thanks Glyn M Ruck, that is some helpful info. Replaced both CPSs, they had them in stock both times I went there, makes me think that it is a common failure. Anyway, I installed them, cleared codes, started the car and ... NOTHING changed. So I call back my SA again, he already knows the whole situation, suggests replacing that magnet camshaft adjuster, since yet another code was thrown (P0010). So I was like OK it's not that bad only like $20. Bough it (also had in stock) installed it, and NOTHING. At this point I am both raging and disappointed, schedule an appointment to service and tow it there. They hook it up to see whats up and tell me it needs new wire harness. w...t...f... man. I said screw it I am done fixing it, just do whatever you need because I need the car by Monday. So will give you an update tomorrow night.







Oh yeah almost forgot the preliminary estimate for the job is $1600 (), with the sensors I already bought and installed, its well over 2K, I just hope new wire harness will be it.

 

Hopefully that's just the engine harness they mean. Price is high no doubt due to time involved in the replacement. I would have a go at MBUSA. A wiring harness should not fail in the time you have had the car. We had a car on the 203 forum a few months back that rubbed through it's main wiring harness where it comes through the firewall - also a V6. Not good & yet I have a friend in KL Malaysia with a 240 like mine with over 700,000 Km troublefree on the clock & we have an E240 in airport duty at the office approaching 600,000 KM trouble free. The lady of the home's 204 is thus far without fault.

 

Problem is, he's been digging around the wire harness so its easy to point fingers and say that could be the cause.

Maybe the TPS was the bad part but after digging around he damaged more.

Chances are no, but if MB USA hears that from the dealership "customer toyed with wiring harness" they might see a big red flag.

either way, there's zero reason to not call MBUSA, hopefully they'll step it up and take care of you.

Make sure you post the outcome!

 

Yeah - but all he's really done is unplug & replug things - The harness should not give in due to that. We don't know for sure it's harness trouble. USA dealers seem utterly useless when it comes to diagnosis. Time spent on this board amazes me - They really don't understand the cars well. There are of course exceptions thank heaven.

 

Doesn't matter how much work he did, if he gets the right dealership they'll tell him tough luck, you clearly touched it so no chance MB will warranty it.

Hopefully that's not the case, but I've seen it before with other car forums. Random person tries to figure out a problem that left signs that he's messed with something, dealership says, hey, you caused the problem.

I for one would tell them to go F themselfs and prove that I caused it. but that's just me =)

 

Is the C350 a Flex Fuel Car? I had a Ford Ranger Flex Fuel bought used. Always filled it with regular fuel until Shell station down the road started selling E85 fuel. After maybe 6 months of using E85 I started getting misfires in multiple cylinders. My friend replaced the fuel injectors to the cylinders that misfired and it fixed the problem. I was able to get the car smogged then sold.

 

Hi guys I have a problem with my 2009 c180 k few days ago I pulled away from a red light and the engine light came on and the car was very sluggish and shaking I pulled over and turned the ignition off and back on again to no avail I've changed the plugs and attempted to check the coils and it still has the same shaking I plugged in the code reader and got the following P0303 P0301 P0300 can anyone please help I'm out of warranty and I've run out of ideas

 

Had the exact same problem today on a 2009 C300 (VIN 9R060501) and the cause was deterioration of the insulation on the engine wiring harness and secondary failure of the 'ME' from multiple short circuits.

 

removed

 

reading fail. removed.

 

Hi I apologize I see the post was a few years ago but I am having a similar issue. Did you resolve the problem? If not how did it get resolved? Any info you share will highly be appreciated

 

Replaced engine wire harness and ME in this case. Problem solved.