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Hey guys, this is the second day that I've had the cobb rmm on my 2015 focus st, at idle and especially with the AC on I'm getting a weird rattling/intense vibration from what sounds like the bottom end of the engine. I can also feel a little of the vibration when shifting at a low rpm. Any ideas of what this could be?
 

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Vibrations (especially when running the A/C) are normal after a RMM upgrade. The mount will usually break in after about 500 or so miles, and the vibrations should lessen some. If the vibes are super intense, check the install.
 

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You're kidding, right? If you had investigated RMM's before installing you would know that NVH (noise vibration harshness) is the main reason people end up removing them. Keep it for 1000 miles at least to see if you get used to it or if it "breaks in." I don't personally feel like they ever break in; you just get used to it.
 
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You're kidding, right? If you had investigated RMM's before installing you would know that NVH (noise vibration harshness) is the main reason people end up removing them. Keep it for 1000 miles at least to see if you get used to it or if it "breaks in." I don't personally feel like they ever break in; you just get used to it.
I agree, I have had mine for probably 20k miles now and if I have the AC on I definitely get some vibration until I start driving then it goes away. I'm used to it now and I figure it is worth it for the car fighting me less. Just my $0.02 though.
 

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Hey guys, this is the second day that I've had the cobb rmm on my 2015 focus st, at idle and especially with the AC on I'm getting a weird rattling/intense vibration from what sounds like the bottom end of the engine. I can also feel a little of the vibration when shifting at a low rpm. Any ideas of what this could be?
There is a compromise between factory and aftermarket; factory is like a sponge but no vibs. Aftermarket nice and firm with vibs; I went ahead and did all 3 mounts using Turbo Tech uppers with the Central Florida Motorsports adjustable lower. The vibs definitely are a bit more noticeable, but the car feels very solid.
 

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You can change your idle RPM to combat this. Many people like what 950rpm feels like. (stock is 850 RPM)
 

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How can i change the idle RPM? Have a Boomba RMM laying here waiting to get installed :)

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