W205 C63s RPM issues?
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W205 C63s Sedan
W205 C63s RPM issues?
Hi all,
I recently got the c63s and it’s been great. Randomly today when I started it and put it in reverse the revs starting jumping really high and low and I was stationary, and I mean to the point the car was shaking. I just the car off immediately and turned it back on and it was fine. Has anyone experienced something similar?
I recently got the c63s and it’s been great. Randomly today when I started it and put it in reverse the revs starting jumping really high and low and I was stationary, and I mean to the point the car was shaking. I just the car off immediately and turned it back on and it was fine. Has anyone experienced something similar?
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2019 C63CS
RPM instability can have a number of causes:
- Faulty fuel injectors
- Faulty spark plugs
- Defective fuel pump
- Defective air flow sensor
- Dirty air filters
- Vacuum problem
- Faulty electrical components
Out Of Control!!
Joined: Nov 2018
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From: San Francisco Bay Area
2019 C63CS
Out Of Control!!
Joined: Nov 2018
Posts: 11,468
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From: San Francisco Bay Area
2019 C63CS
Any of the above. As said, read out the codes and hopefully it'll point you to the cause. For reference my previous car developed cold start misfires around 35k miles out of the blue. Never got it resolved until I sold the car. Doing a carbon clean improved it, but never went away completely, but it was clearly partially caused by carbon deposits on the intake valves. I would also get violent shaking after cold starting the engine, and then I immediately turned it off and usually on the second start it was fine. Also it happened primarily with winter fuel blends. Never really happened during the summer months.
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2019 C63CS
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Out Of Control!!
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From: San Francisco Bay Area
2019 C63CS
Means your spark plugs are shot. Covered in substance like oil, fuel or carbon or blistered from running too hot. Tunes overwork the stock spark plugs and they don't hold up for the expected stock interval changes. You'll have to change them more frequently or use aftermarket spark plugs that hold up better.
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W205 C63s Sedan
You’re an absolute legend, it that common to happen? My service is due tomorrow so everything will be checked over. I believe it’s the stock plugs, it also had a dyno run 3 weeks ago so it’s probably fried them? What I’m confused about is why the problem when away when I turned it off.
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From: Maryland
2018 C63s
You’re an absolute legend, it that common to happen? My service is due tomorrow so everything will be checked over. I believe it’s the stock plugs, it also had a dyno run 3 weeks ago so it’s probably fried them? What I’m confused about is why the problem when away when I turned it off.
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W205 C63s Sedan
@BL4DE
it could have clipped to neutral, it that common to happen if it does? I purchased it turned, and I haven’t had the issue again. It’s going for a service in the next couple of hours so maybe they can tell me something.
Thanks
it could have clipped to neutral, it that common to happen if it does? I purchased it turned, and I haven’t had the issue again. It’s going for a service in the next couple of hours so maybe they can tell me something.
Thanks
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From: Virginia
C63s Coupe
Yes its possible. if you don't push the shifter hard enough into reverse, it will go into Neutral. I've done that a few times and the car will rev, as you described.
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c63 S amg
