Alex Dee

hi

I have a 2007 c230 sedan (2.5L), and over the past few weeks in ontario i have noticed as the temperature has dropped the car has been harder to start (starting very rough as if only running on a few cylinders) to the point where the car is not starting at all.

before all of this started i got an engine code to replace the cam shaft sensor, but after a little research i found out the sensor was fine it is actually the magnet that was triggering the code, anyways replaced magnet and CEL went away.

just now i pulled a plug from the motor and it smelt of gas, also i tested the spark and there was spark.

Ive read several threads with similar problems and no real conclusion drawn can any one provide some guidance?

thank you

VVF

I don't know the symptoms of balance shaft issues, but have you checked your engine serial number against the bulletin?
See https://mbworld.org/forums/c-class-w...aft-issue.html

Alex Dee

I cannot load the image with the vins to be weary of, but as a update, I pulled every coil/spark pug to test spark and fuel. And every cylinder is producing spark and fuel. I also tested the throttle body to see if it was functioning and It was, the only thing left Is timing BUT I'm not throwing any codes , so I don't know what to change. There is a service notice on this car to change the harness to the cam sensor but the dealer wants to charge me diagnostics for something that there probably responsible for I'm guessing

KSKarl

Check for vacuum leak, or a leak between the MAF sensor and throttle. That could make the mixture too lean to run when cold, though it might still run when warm.

Alex Dee

it was really tight when i pulled it apart. i just started the car this evening +7 outside right night now, anyways, its throwing a bunch of codes all related to the mass air flow sensor and the oxygen, i suspect because i was spraying the **** outta the MAFsensor with quick start ( which by the way the car did;t even cough and we all know how deadly that stuff is ) should this car start if i unplugged this MAF sensor in some kinda limp mode? because i did that aswell earlier in the week and it did not start, also the oxygen sensor code i suspect because i have been flooding the engine the past few days in the cold, besides the oxygen sensor has nothing to do with the car turing on.

I really think it is a timing issue, although i am not throwing any codes. that or there is somkind of service campanige against this car that has to do with the harness to the cam sensors (or something like that the dealer was vague on this topic) which i would be related to my theory.

please note i was not getting a single code before.

thanks

Alex Dee

well i am now getting a whole **** ton of code, none of which i can see having to do with the car starting.

P2158 vehicle speed sensor B
P0040 powertrain
P2273 Power train, O2 sensor signal stuck rich bank2 sensor 2

P1373 powertrain
p0925 powertrain
P0600 powertrain
P0515 powertain
U0121 network

Also(R) terminal 87 relay, engine (n10/1kR) is clicking when the car is shut off, i switch the relay with another relay to see if it was the relay it self and the same thing is happening.
also the coolant fan is running at high speed when the car is off after 5 min of sitting, so i am starting to think the ECU is going wacky.

any help will be greatly appreciated.

Alex Dee

update,

it appears it was the coolant temp sensor, i tried to start the car one cold morning twice and the same stuff was happeneing. so i unplugged the coolant temp sensor that is on the back left side cylinder head. the car started up with some hesitation, i have since replaced the sensor and no complaints as of yet.

Alex Dee

well, as a previously stated, the car started after i unplugged the coolant temp sensor. But i am beginning to think it only started because it put the car in some kind limp mode ( forgive me i am not super familiar with MB) regardless the car won't start now.

I replaced the plugs, because after i was driving the car around in above freezing tempatures, when all the sudden the car started mis firing throw p0300,0305,p0306 which by the by is all on he driver side head. regardless i replaced the plugs after the car sat for 3 days, but they still STUNK of gasoline. i know i flooded it before, bug maybe its my intake air ten sensor? i am running out of ideas. i replaced the plugs because i thought i fouled the plugs earlier in this diagnostics and i assumed this would fix the mis firing, unfortually as you know now the car won't start so i am running short of ideas.

IrishCClass

Make sure the air intake box and elbow that connects from the air box and the throttle are clean and connected all the way. I had some cold start issues and it was due to a dirty trottle body causing the plate not not index properly as well as too much air flow. Combined with cold temps it was WAY to rich to start.

Alex Dee

I checked all that, so I gave up and sent my car to a mechanic, he said it was the first O2 sensor, which is actually a wideband( which I was surprised I did not know that these cars had wideband) anyway car ran great for 1 day. the very next day same Sh*t, hard to start got 1 new code 4 ghost codes,
P0175 has the hard code, system too rich bank 2 ( driver side cylinder head)
Ghost codes:
P0342 Camshaft position sensor "A" circuit low???
P2094 B camshaft position actuator control circuit??
P0746 Pressure control solenoid "a" performance stuck (apparently a tranny code)
P2092 A camshaft position actuator control circuit??

What boggles me, is that if I am running rich in bank 2 which is governed by Cam shafts "C" & "D". why am I getting code for Cam shaft "A" and "B".


This is my first benz, and its been a hard time. BTW car has >100,000KM on it.

BATComm1

Any word on this my 2007 C230 is doing the exact same thing!!!

Alex Dee

so i went through a horrible time with this whole thing, the mechanic i sent it too is a specialist and he tested every componetent relating to starting and he said everything was working properly. his final conclusion is the computer is Trash ( he did re-flash the eCU). what he said is that i am running too rich so if you are poring white smoke when you get the car started, or it just stink like gas, you have the same problem i do.

BATComm1

Yup it poured white smoke this last time it started. .did eventually clear up but now won't start again...

Alex Dee

Got my computer in, car started in -15. i has never done anything close to that for me ever

BATComm1

That sounds promising for you..I'm about to that point of trying an ecu...you don't by chance have the part number or source where you got yours?

Alex Dee

Well I am from Canada so I got my ecu from Rush auto parts, in order to know the correct part number you have to read it off the physical computer itself because even for the 2007 there are several computers. and calling Mercedes benz and asking them for the number will not help you because in most cases they will release a newer version of your computer (vin specific) and will not help you get a used one, I know I tried doing that.

Please remember that just because my computer failed, it does not mean it is necessarily yours, you really should check your coolant temp sensor( the sensor on the back of the driver side head and not the one in the t-stat housing) and primary O2 sensors ( wideband's) and the mass air flow.

this is a painful problem because regardless of what you replace it is not a guarantee. the computer ran me $508 CND with tax, the windband sensors cost ~$310CND, and the coolant temp was ~$31 make sure you get it from the dealer. just a heads up.

If you have trouble getting your specific computer number I may be able to help you out, I called another parts place and gave them my vin and they double verified my computer number so there is another option.

BATComm1

Very true Alex, just getting a head start, after reading other posts here and other forums I've ordered up a MB temp sensor and gonna give that a try should be here on Friday....

Alex Dee

good luck

BATComm1

Well I went out yesterday morning to replace the coolant temp sensor, just for giggles hit the key and nothing..so I proceeded to look for the coolant sensor, while looking for it on the back of the head I noticed that the new crank shaft position sensor I had installed was not completely plugged in!! ...plugged that in and she fired right up!! but still had the stumble and fuel rich exhaust as before..so I let it run and decided to go ahead and replace the coolant sensor, did this and it has started ever since every once in a while still with the stumble...so I still have a problem but it runs, I'm just waiting on a code to come up so I can see what she tells me.


Thank you Alex for your help!!!!!

Alex Dee

hey man, be careful. my car is now knocking in cylinder 6. i still haven't found out what exactly is the source of the problem. but it may be from running to rich and fu**ed a crank bearing. so i would;t not recommend running the car too rich for long.

BATComm1

Holy crap!! Well I went out this morning and hit the key, started just fine no stumble, just smooth start...I hope it keeps it up. Sorry to hear that on yours that really sucks. .I did get an o2 sensor code P2273, so I'll get that ordered up soon...

IrishCClass

Further update. I believe everything is coming from on a leaking oil separator it has been sending oil into the throttle body and intake. ECS tuning makes a replacement kit to fix this. It also will lead to oil getting into the converter causing a O2 code as well. Check for an oil leak on the rear right side of the engine possibly coming from the rubber hose between the cylinder head and the intake.

alika808

I am just wondering how much it cost you the ECU? Also, do you need to reprogram the ECU with the car, I asked this question because in the BMW, when changing the ECU, the EWS and key chip should be synch with each other. Thank you.