gonna try and keep this as short as possible. I have experienced this weird jolt/jerk in my '16 glc300. there are a few threads about it, but wasn't sure how they would really help. the jolt feels like a manual car about to stall and the jolt is hard enough to make you feel as if you might have been rear ended. it even frightened the life out of my passenger once! so far in the 3 years of ownership and 20,000 miles (low mileage cars where we live), I've only experienced this 4-5 times. the check engine light came on thrice, but went away within 24 hours. my mb dealer has zero clue and I tried another dealer who really couldn't help much either. I've tried recreating the problem, to no avail and as I said the check engine light went away before a tech could come and scan it. I love this car to bits, though this issue is unsettling to say the least. any help/input is appreciated

 

Not had this problem on my GLC but it sounds very similar to a problem I had with my W205.

When it happened to mine the engine light came on and it went into limp mode. After turning the engine off I managed to get it out of limp mode but the engine light remained on.

The dealer replaced a wiring harness in the engine bay - I can’t remember which one and they just told me there was an issue with it.

Sorry I couldn’t be more specific but it was a couple of years ago and no longer have the car.

 

thanks cbc200! mine, too went into limp mode once, though the rest of the times, it was just the check engine light. and it did come out of the mode with check engine light still on after I started it again. will note this and hope more inputs come in and then head to my dealer. thanks again!

 

My recommendation is to get a cheap OBD code reader from Amazon and keep it in your car. Next time it happens, use the reader to find out the code so you have more info for the dealer.

Here's an article that in the middle tells how to check the OBD code. http://www.mercedesmedic.com/mercede...sfire-problem/

 

The shift module in my 2016 GLC 300 4MATIC failed. Symptoms included jerking, no response from accelerator. The transmission basically doesn't shift properly and then causes the accelerator to be non-responsive. If it happens again manual shift to a lower gear to see reaction. My 2016 was plagued with more than its fair share of issues: failed sensor connector for rear, shift module, pinched ignition wire harness causing engine misfire and not driveable. All of this was fixed under warranty, but made the first 8 month of ownership questionable. Now I need to tires and trying to find a GLK spare and jack so I can ditch the RFTs.