Hi, I bought a 2017 C63 a few month ago and It's been running great until today. Suddenly at the stop light it started to idle really rough and check engine light came on. I had a friend with a generic scanner plug it in and a bunch of codes appeared. P2A0B, P2279, P152C, P2180, P0300, P0308, P0305, P0306. We cleared the codes and they came back again after 30 minutes drive. The car is stock and out of warranty, I'm just wondering if anyone had similar experience and what might be causing it.

Thanks

 

How many miles are on the car? How many miles on the spark plugs? It might be due for a new set.

 

55k miles. I should've also added that this happened ~10 miles after I filled the tank with 93 octane from Costco, could it be bad gas?

 

It could be bad gas. Since that's easiest to rule out, fill up at a different station when you need gas again and see if the problem persists.

 

Had this happen to me when I had my Audi. Took it to dealership and they tested the fueled. Told me the gas in the tank was less than 87 octane even tho I had filled up with 93. I figured there was prob some sort of contamination in the fuel at the gas station. However, I typically fill up at Exxon, Shell, BP or Marathon. Havent had any issues so far on the Merc.

 

I run Costco 93 octane - for several years no problem. It's a top tier brand. Also because of the volume sold I know I am getting fresh gas.

 

It's could be bad gas. When I pushed the button for 93, the blue light above it wasn't on as usual. I questioned one of the attendants and he told me the light is out confirmed from the price that I was getting 93. Maybe it was a malfunctioning pump and I got 87 instead?

 

Bad gas from the sounds of it. Have you cleared the codes yet? Did they come back at all?

 

I also have a 2017 and had the same problem, looks like most of the same error codes. I trouble shot and took it to an independent sop With no luck, ended up taking 2 dealer and they fixed it with an updated Flash. The service advisor said that this happened frequently due to cars needing the software update.

You can search my old posts on this forum for more info.

 

Thanks, I found your thread.

So I had about 1/2 tank left and filled with 93, added a full bottle of octane booster and drove a about 15 miles to run through any "bad gas" in the line. The car drives normal on the highway, but it's still a little rough at idle. If I keep it in sport+ which keeps rpm higher, It idles normal and I don't get any codes. If I switch to comfort, it idles a little rough and I get some codes. I got P2279 and P152C after driving in comfort for a few miles, including a few stop lights idling. I'm starting to think it might be vacuum leak somewhere. I will see if I can find anything, otherwise I will take it to the dealer.

 

 

Most accurate thing I have seen in a long time. Hahaha.

 

Im having same issues anyone find a solution?

 

Check the Canister purge valves in the engine compartment on the left side. One of them might be sticking intermittently causing your problem. Disconnect them electrically and see if your rough idle goes away. You can also pull the hose off the side that goes to the gas tank and see if there is vacuum on the nipple. If there is you got a stuck open purge valve.

 

Any update on these vehicles? My c63 just started the same problem and codes about 10 minutes after fueling up. Just drained the tank and got better fuel. Still misfiring on idle very bad

 

what was the problem?