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What’s going on guys. New to this forum and Mercedes’ at that matter. Come from the LS world. I have a 2011 E350 4 matic that is starting to be a pain in my side. Bought it used as a back and forth car for the weekend. Cheaper to fill then my truck. When i bought the car it had some issues. When driving especially cold not fully warmed up the car has some shuttering and rpm surging. I’ve looked far and wide over the web and have found multiple things that could attribute to these issues. Started with intake manifold. Found the intake runner flap actuator linkage broken. Replace with new OEM intake and gaskets. Replaced cam and crank sensors as a preventative measure (one sensor was leaking). Replaced gas cap. Did new plugs a long with a few odds and ends. It only happens between 10-45mph. If throttle is pegged issue goes away. The longer the car is driven the better it gets. No codes thrown from engine or trans module. Checked with autel maxipro MP808 bi directional scanner. Throttle position stays steady, maf reads steady, everything seems fine. Only question i have is what are you guys reading for EVAP pressure during idle? I’m sitting around .5” H20. Seems a bit high.
all in all starting to pull my hair out with this thing. Any help would be appreciated.
Having done some troubleshooting and maintenance you are in a better position now.
My experience regarding EVAP is it's is very closely monitored and one of the first system to produce a code in the rare circumstances it leaks.
You are confident your ignition is good and no codes are pending. So it's a subtle problem not a massive faiure.
Unmetered air leaks tend to get compensated but unavailable gas has no replacement.
I am leaning towards fuel delivery issue (pump, filter, O2)... have a look at your shorterm FUEL TRIMS data while driving in relation to surges: any indication of a lean engine getting enriched?
Is your MAF sensor nearly clean?
Last edited by CaliBenzDriver; Dec 27, 2021 at 08:20 PM.
Having done some troubleshooting and maintenance you are in a better position now.
My experience regarding EVAP is it's is very closely monitored and one of the first system to produce a code in the rare circumstances it leaks.
You are confident your ignition is good and no codes are pending. So it's a subtle problem not a massive faiure.
Unmetered air leaks tend to get compensated but unavailable gas has no replacement.
I am leaning towards fuel delivery issue (pump, filter, O2)... have a look at your shorterm FUEL TRIMS data while driving in relation to surges: any indication of a lean engine getting enriched?
Is your MAF sensor nearly clean?
maf Is clean as well as throttle body and 90* elbow. New air filters as well. I have zero misfires after plugs. I will have to take some freeze frame data tomorrow watching the shore term fuel trims. The long terms for both banks was sitting around +8 during 45mph cruise and surging. I honestly can’t remember what the short terms were doing. It’s just very odd. When the car is driven around ALOT during the day the issue seems to dissipate for the most part. I don’t drive the car every day since i have a company truck. Either it’s a coincidence or a clue, i was having zero issues around half a tank. Filled up and the issues came back. Watched purge percentage and issue came when purging. Unplugged purge thinking maybe charcoal canister might be bad. Issues went away about 90%. Drove fine the rest of the day. Let sit over night and cool off and boom happens again. It’s just so intermittent and every time i fix something it seems to help then once a heat cycle is complete boom it happens again. I was starting to lean towards maybe converter but no codes or issues in trans that i can see. Fluid temp stays in range. I’m pulling my g darn hair out lol. I’m not a mechanic but i know my way around a car. First German car and it’s making me miss me Pontiac G8 lol
You mentioned that the throttle position stays in place but what about if that signal is bad and the car keeps moving the throttle to keep that signal showing that it does not fluctuate when it actually does?
What’s going on guys. New to this forum and Mercedes’ at that matter. Come from the LS world. I have a 2011 E350 4 matic that is starting to be a pain in my side. Bought it used as a back and forth car for the weekend. Cheaper to fill then my truck. When i bought the car it had some issues. When driving especially cold not fully warmed up the car has some shuttering and rpm surging. I’ve looked far and wide over the web and have found multiple things that could attribute to these issues. Started with intake manifold. Found the intake runner flap actuator linkage broken. Replace with new OEM intake and gaskets. Replaced cam and crank sensors as a preventative measure (one sensor was leaking). Replaced gas cap. Did new plugs a long with a few odds and ends. It only happens between 10-45mph. If throttle is pegged issue goes away. The longer the car is driven the better it gets. No codes thrown from engine or trans module. Checked with autel maxipro MP808 bi directional scanner. Throttle position stays steady, maf reads steady, everything seems fine. Only question i have is what are you guys reading for EVAP pressure during idle? I’m sitting around .5” H20. Seems a bit high.
all in all starting to pull my hair out with this thing. Any help would be appreciated.
Hope you figure it out, but where did you get your grill? I love it
You mentioned that the throttle position stays in place but what about if that signal is bad and the car keeps moving the throttle to keep that signal showing that it does not fluctuate when it actually does?
Just a thought…
The thought was in my mind. Just hard to tell. The throttle body actuator readings stay steady as well. Plus it’s only in a specific RPM and MPH range. I would think if the signal was bad then it would do it the entire time. But who knows lol.
What about the pedal itself, have you check voltage and percentage rate?
percentage rate and voltage stays steady no issues. I was watching that too. Anyone know how many inches of WC the car should make at idle? During idle i drop no lower then -1.8”WC. Seems like that is a bit high.
E1,
If your scanner has Mode 6 ( OBD2 standard ), try running it. It can show data where is not yet reaching threshold of Check Engine Light.
Mode 6 covers a lot of parameters.
Last edited by S-Prihadi; Dec 29, 2021 at 07:05 AM.
Now that everyone got the grille thing figured out, I would attribute the surging to an unmeasured air issue. When intake systems get old and crack post/downstream of MAF the same symptoms present, along with lean conditions (in case you can monitor fuel trims and O2 sensors). It also makes sense that as the engine warms up and things expand, the leak is sealing up. If no codes, try a smoke test or look for common intrusion areas. M272 not being too distant from 276 (although 276 uses MAP sensors and has no MAF) I am not familiar with 272 intake. Get WIS/EPC on eBay and let us know what you come up with.
Now that everyone got the grille thing figured out, I would attribute the surging to an unmeasured air issue. When intake systems get old and crack post/downstream of MAF the same symptoms present, along with lean conditions (in case you can monitor fuel trims and O2 sensors). It also makes sense that as the engine warms up and things expand, the leak is sealing up. If no codes, try a smoke test or look for common intrusion areas. M272 not being too distant from 276 (although 276 uses MAP sensors and has no MAF) I am not familiar with 272 intake. Get WIS/EPC on eBay and let us know what you come up with.
thanks for the input. I reset the fuel adaptations as well as the trans. Looking at the short trims they were very back and forth. Depending on gear and throttle position. Very erratic before resetting them. Now its pulling fuel out no matter what gear. I’m no mechanic by any means but i have recently been leaning towards some kind of air intrusion after the maf. Now i don’t know how the Mercedes are but all the gm stuff I’ve worked on while at idle pulled a decent vacuum at idle. While not opening the purge valve the car sits at +.5” H20. Whole purging it gets down too -1.9” H20. When cruising around 45-50mph in overdrive I’m at -9/-10” H20. Seems to me like there is a leak somewhere. Fuel pressure is fine at idle and under load. Pressure doesn’t change in the rpm range so i don’t think it’s a fueling issue. Plus no misfires so I’m guessing the injectors are operating properly.
I'm not sure because I haven't looked, but (and I think it is) if the 272 is anything like the 278/157 then there's not much after the MAF, as it sits only about 5" upstream from the TB. Sooooo hmmmm....
So at this point I would suspect throttle position sensor and/or TB sensor, or a bad MAF. A bad MAF won't always throw a code. I would start with a MAF sensor, cheap eBay, OEM, used or other, doesn't matter, and reassess function with the new maf. If the MAF element is taking a while to heat up for whatever reason, that would explain why the ECU is getting bad data until it warms up.
its been a minute since ive replied. After all of my troubleshooting i decided to do a trans fluid change just for maint reasons. car has 90k on it with the 70k mile (A89) fluid in it, never changed. low and behold my surging issues are gone. the fluid was BLACK and the filter was plugged. only minor metal dust in the pan, no chunks. All in all the intake manifold (needed due to flap linkage broken), crank sensor, cam sensors (all 4), new plugs and boots, as well as a few other parts changed along with the trans fluid now and she runs like almost brand new. Bi directional scanner never through a code for any issues, trans nor engine. only issue i found that lead me to fluid was the fact that while watching tc lockup on the scanner it never fully locked. just glad its finally running correctly lol. Thank you to everyone for the feedback!
Nice to see you got it fixed and appreciate your feedback . I am not a technical person gifted with lots of Edward China skills but I like to see such feedbacks on the problems
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