randyboy

2016 E350 89k miles
i’ve got a weird situation going on. While driving the vehicle, check engine light flashed and remained on. it starts rough idling and with an obvious loss of power. I turn off the vehicle checked engine light is gone and the car drives flawlessly. I brought to the Indy mechanic and nothing shows up on the scan. Has anybody had this intermittent issue?

CaliBenzDriver

... and indy is using what scanner version you said on you 2016 Euro import??

I can hardly believe this whole situation has no code.
Before further troubleshooting, I volunteer this is a bus crash originated by one of the busy module, likely solderless.
In the end ECU/TCU COM's are impacted with other distress nodes traffic. I have a short list in the back of my head.

The long story short is a better scanner would yield greater coverage. Either by a decent $150 LAUNCH scanner or contact @BenzNinja for his personalized remote services.


I can see a new battery comming your way with perhaps the fake "AUX" Module being toastd... Dont underestimate the importance of clean power supply for 45 computers.

Please get your chassis SCANNED better so you don't get too many good parts replaced without improvement.

JettaRed

iTrader: (1)

If you are going to own a Mercedes, you need to be flush in cash OR become somewhat your own mechanic. You need to at least get the right knowledge and tools to diagnose your problems to understand what is required to fix something (or get a lifetime membership with @BenzNinja who can remotely diagnose and fix your car if it's a configuration problem if you have no mechanical skills). For example, I don't need to actually be able to repair a transmission, but I do need to be able to determine a problem shifting is likely my transmission.

juanmor40

Bang on!!. As owners of these computers on wheels, we need to separate Root Cause from Repairs. Most of the "booked time" is on the diagnosis side, once diagnosed (the earlier the better), the repair should be straightforward though not necessarily cheap.

bumparker

Similar issue on 2014 E350. However, flashing check engine means major issue and stop driving, solid check engine means there is a stored code. Something should be stored. That will lead you to the problem.

My guess (my problem too) is that you have an intermittent misfire. The stored code will tell you which cylinder. Replace that coil on plug and spark plug once you know which cylinder is the culprit.

JettaRed

iTrader: (1)

Correct! Flashing means a serious current problem, usually severe misfires. You should not drive without knowing what caused the problem. That's why I keep a Mercedes-specific scan tool (LAUNCH Creader Elite BENZ) in each of my cars. Knowing the cause (from the DTCs), I can then decide whether to drive the car or call a tow truck.

I once decided to clean the engine of my 2000 Ford F150 when I purchased it with 205k miles on it. Water got into the spark plug access hole in the head when I rinsed things off and shorted out the coil. My CEL flashed like crazy when I took it for a test drive. My trusty and in-car scan tool told me which cylinder was misfiring. Removing the coil and seeing water down the hole, I blew it out with compressed air and all was fine thereafter.

JettaRed

iTrader: (1)

Double bang!

BenzV12

Sorry to hear about it and I was not aware of check engine warnings either . Intermittent problems are harder to detect . I had a check engine light come on in my first W212 . A regular scanner failed to detect it but an independent Mercedes-Benz found the glitch using their special tool

Arrie

Very good responses from members. I would add that it could be the crank shaft of cam shaft position sensor that can cause misfire if that is found with the scanner.

JettaRed

iTrader: (1)

Here's a good video that shows not all scanners are the same. It shows that if you buy cheap, you get cheap. I would not buy any of the ones recommended for work on a Mercedes (though I did buy the ANCEL AD410 years ago), but it does show how some scanners would not find faults in anything other than the engine module. Kinda worthless for anything other than identifying which cylinder misfired.