ejmb2010

So my E-350 sat for 24 hrs in sub-freezing cold. It started up but seemed to be missing I drove it a short distance and the check engine light came on. I made a short stop, shut the car off for 10 mins when I restarted the car all was good. No missing, no CEL.
Anyone ever had this happen?

homeofstone

Similar problem here with a 2007 e350 and it was the crankshaft position sensor.

raymond g-

almost impossible to conclude anything. here is why: CEL comes on for a
variety of reasons. the hundreds of sensors aid in providing feedback to the
many interrogation systems, one of which monitors for CEL alerts. some of the
triggers may be transient and disappear. the CEL may log the error code but
not light up as it views the error as a 'false positive.' if an error code repeats
then the CEL lights up. if, within a relatively short time, the code vanishes,
so does the CEL.

OBDII code readers can be had for as little as $25 or so. It would be similar to
owning a volt meter, ie always good to have one if you're the type of owner
who likes to understand why something is happening to your car vs someone
who would rather turn the car over to a dealer to perform the diagnosis

Mrkoopz

Cold Temp always triggers the most unusual error/warning codes, i really hate it, the car relies on so many digital sensors that with cold temp, it just goes whammy. i would take raymonds advice to get OBD code readers and see if the error code shows up. If it doest then, no need to worry, thats what the dealership check anyways and you don't want to spend 120$ of diagnostic for something you can check yourself....

noka

OBDII code readers are OK but results are often vague and don't pinpoint the exact problem. The MB dealer has more sophisticated equipment to further evaluate the problem. You will likely end up taking it in for service to get it fixed anyway.

Arrie

Guys, (Mrkoopz and raymond g-)
there are no hundreds of sensors to set the CEL.
The car has Mass Air Flow Sensor(s), Intake Air Temperature sensor(s), Intake Manifold Pressure sensor(s), Crank Shaft Position sensor, Cam Shaft Position sensor, and Oxygen sensors before and after each catalytic converter in the tail pipe. In a car like ours with dual tail pipes and catalytic converters and dual intakes it means 12 sensors max. I don't think they use two sensors for temperature so it probably is just 11 and if they don't use Mass Air Flow sensors it brings it down to 9 sensors. Some cars use fuel tank pressure too so this could bring the number of sensors up by one. In any case there are no hundreds or even tens of sensors.

CEL is an indication for emission control system not working properly. The OP says he got the CEL after a short distance of driving. The key here is how short. From cold temperature start it can take quite long drive before the fuel control system goes to closed loop control as the catalytic converters must heat up to working temperature. This means that the CEL will not be triggered by the normal emission sensors right after start. What can trigger it very quickly is misfire (no specific sensor) or the crank shaft / cam shaft positio0n sensors. All of these can be triggered by moisture for example.

The OP should read the saved code. The light went out but there should be a saved code to read of what set the light.

Some auto part stores like AutoZone read codes for free. They will not reset it and good so as it will be for MB to read too.

ejmb2010

Thanks all I will get the code read and let you know...

Rocman8

its actually very common in the cold for there to be a misfire right after startup that goes away after a cycle of the key. its really annoying but nothing to worry about if it was indeed a misfire. more common on the m272 and m273 than any other benz engine in my experience.

raymond g-

if you're careful, you'll note that I didn't claim this

pamiboy

On casual reading I got the impression that there are hundreds of sensors. Now we know that you didn't mean it that way and fully appreciate the technical information you shared. Thank you.

hyperion667

anyone notice how many CEL's are illuminated these days? I swear: when I'm on the highway lately I can see everyone's CEL on LOL

dbldpr

Auto zone or o'reilly or just about any parts store will read your code for free Go there first because the dealer will charge you to read it unless it is under warranty.

noka

Realistically though, won't you be taking it in for service (dealer or independent) anyway even if you have a code? What would you do to fix the problem on your own with the code?

dbldpr

actually I am quite capable of replacing almost anything on the car. I even own a rotisserie to put the car on. I have restored several old cars. I know a lot of members are not as capable but at least they will know what part is bad and then decide if they can fix it for themselves.

noka

Must be nice to be able to do that. I'm suitably impressed!

hyperion667

having the code would be no help?
knowing the code would be a big help to, get a cost estimate, and make sure they don't try to tell you
something is wrong that isn'tan OBII tool is great to have....although I don't have one either

noka

If it was possible for you to see some code that the tech might not see, then I could certainly see some value in providing the tech a hint. I don't know if that's a possibility or not. I agree that if someone was concerned that their service facility might rip them off, then having a code might be of some use. While I am not naïve, I really don't concern myself with such things where I get my car serviced.

mleskovar

If the CEL trips then there's a stored code even if the CEL goes out. Be careful when looking at stored codes with respect to the date stamp. If the codes haven't been cleared in a while you can have many old ones that aren't relevant anymore.

Rocman8

there are really cheap elm327 wifi or bluetooth obd2 connectors that you can get on amazon and just use an app like "torque pro". you can read codes and most actual values live. this can be as cheap as 20 bucks.

BenzV12

You should visit a dealer or indie shop with a DAS STAR TEK Device .You may not see any fault codes but DAS can read .
In your case, I believe cold weather must be the culprit

Arrie

Direct quote from your post:

"CEL comes on for a
variety of reasons. the hundreds of sensors aid in providing feedback to the
many interrogation systems, one of which monitors for CEL alerts."


How should I understand this?

Arrie

I believe that a OBD II scanner that everyone can buy can read all of the codes that can set the CEL. CEL is related to engine fuel performance and in my understanding is government mandated feature. At car inspection the scanner they use reads the same codes. No specific high end scanner needed.


DAS STAR TEK or other high end devices read all sort of codes beyond the ones that set the CEL. This is how I understand it.


Different states probably have different rules for this too at inspection. When the CEL is lit in my state they scan the car and if there is only one code that set the light the car will pass. Two or more codes it will not.


For folks wondering what help the OBD II scanner is some very easy fixes include gas cap and oxygen sensors. Oxygen sensors are one of the most common problems and in general are very easy to change. This, of course, if the car is outside warranty. Gas cap is no brainer.


When it gets to crank shaft and cam shaft position sensorss I have no idea yet how to do it on the E but have changed these before on another vehicle.


Just bought my OBD II scanner for $130 from AutoZone. Have not needed it yet but plan on using it at the first sign of any issues.

ejmb2010

UPDATE: Took the car to get the codes read and guess what? No codes, zero, zilch. Car is running fine no further issues. Mystery...

noka

Was it an MB tech or tech with MB diagnostic equipment that attempted to read the code(s)?

Mud

First time ever, engine typically runs flawlessly, about a week ago on a 35d morning the engine had an obvious misfire. CEL was flashing, on past vehicles a flashing CEL was generally coil pack related. I stopped and restarted the car, perfect again and also since then. I hooked my scanner later and no codes were stored. Coil misfires don't always store a code or it could have been a one off weirdness lol. Heck I'm like that sometimes.
You can use an inexpensive scanner to read the ECM, of course the mfg will have the ability to read and program to much further depth.
Anyway until or if it happens again I'm not going to worry about it.