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Setting higher idle rpm with Cobb RMM

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130
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Location
Milpitas, CA, USA
#1
Not sure if this is in the right section, but it's a tune question related to the Cobb rmm...

Is there a downside to upping the RPM of idle for the FiST? I've noticed that if the idle sits at around 1K rpm, the vibration due to the Cobb Rmm pretty much disappears. I've found myself nudging the throttle a bit just to not experience all the vibration.

The only downside I can think of us more fuel consumption. I can't imagine another 100rpm to be a dramatic issue from a wear and tear perspective.

I don't have an accessport, but I'm assuming idle can be adjusted on it given it can change fuel maps.
 


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27
Location
SF East Bay
#2
Idle adjustments are possible with an AP3. I just ordered one through Mountune and one of the questions in the custom tune options was a higher idle setting. I'm not sure if the generic Cobb AP3 maps have this option.

Vibrations at idle are the main reason that I will not be buying a Cobb RMM. If I wanted a car to shake and rattle I would not have spent the money for a brand new car. But there are people who bought the Cobb RMM's who either don't experience the vibrations or don't mind them.
 


BoostBumps

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Arizona
#3
I don't think you can setup the Idle Rate with just AP alone...You need to either purchase Cobb's AccessTuner Race (ATR) program and change it yourself (For those folks capable of self-tuning) or have your Tuner setup idle to higher value along with thier custom tune....

And yes....raising idle from current 750rpm (warm) to 1000rpm will have an impact on mpg's...
 


OP
C
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Location
Milpitas, CA, USA
Thread Starter #4
Hrm...would an "idle relearn" procedure address the vibration in the Cobb rmm?

I've read on other car forums that you can do it by disconnecting the ground wire and reconnecting it and performing a series of steps afterwards. I'm not sure if it takes in to account excess vibration or even do anything though since the combustion related equipment didn't change.
 


BoostBumps

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#5
Hrm...would an "idle relearn" procedure address the vibration in the Cobb rmm?
Not likely....

Idle is set to a discrete target value within the ECU...In order to change idle value at warm-up you'd need to change that discrete value entered...In short, the ECU idle is closed loop and as such will always want to come back to the set target value entered..

Idle setup.jpg
 


OP
C
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Location
Milpitas, CA, USA
Thread Starter #7
Yeah the AC definitely does make a difference, unfortunately I live in Houston so the AC is on 98% of the year
 


Hijinx

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Auburn, AL, USA
#8
My Cobb RMM is about a year old. No vibrations even with the AC on.
 


Messages
326
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50
Location
greensboro
#12
Yeah, I notice mine less and less. I think it has a break-in period. I know its not as harsh as some of the others on the market, I daily my car so comfort is an issue. If it becomes a purpose built racecar in the future then I will get a more solid RMM.
 


Izzy

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Location
Houston
#13
Mine is 2 yrs old and it's driving me insane every time I turn on the A/C or initiate reverse. The mount visually looks great...it must be mushy or something. But at 1000-1100 RPM the rattles disappear. I come from having HASPORT mounts on all my Hondas....and none have vibrated as bad as this.
 


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Location
Westchester
#14
Mine is 2 yrs old and it's driving me insane every time I turn on the A/C or initiate reverse. The mount visually looks great...it must be mushy or something. But at 1000-1100 RPM the rattles disappear. I come from having HASPORT mounts on all my Hondas....and none have vibrated as bad as this.
Wow I know every Honda I had with aftermarket mounts made me feel like I was operating a jackhammer. I just swapped a mountune mount in yesterday and it's the first aftermarket mount I've ever put in that has not bothered me. It's not noticeable at all besides the benefits really happy with the unit. I wonder as it wears if it will cause added nvh? I understand everyone's tolerances are different but I was afraid of putting this in the car dreading the added noise but there is none. Might be an option OP...
 


Messages
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39
Location
Indianapolis
#15
I did not notice much difference going from the factory mount to the Cobb unit. I did install it with less than 200 miles on the car so I never did get used to the factory unit. If I hear or feel anything it is with the AC, and as some have mentioned earlier, I rarely turn the ac off.
 


Izzy

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Houston
#16
It's only at idle with the A/C on for me. Thinking of maybe adding some shims at each side and see if that helps any. I'm at a loss really. I've uninstalled & reinstalled the thing at least 3 times now. Tried tried 40ft/lbs, the spec'ed 50ft/lbs, and even 65ft/lbs....nothing works. Really considering having Russ give me a 1000-1100 idle to solve it.
 


ROCKYFiestta

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Location
Colorado Springs
#19
man starting to feel like not installing the cobb rmm. i hate vibrations but with winter coming in i dont need ac until june next year so still on the fence about installing it. maybe it will be broken in and not as bad by then??
 


redmoe

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Location
Phoenix
#20
man starting to feel like not installing the cobb rmm. i hate vibrations but with winter coming in i dont need ac until june next year so still on the fence about installing it. maybe it will be broken in and not as bad by then??
The vibrations with the Cobb are very mild. I ended up gong from the AWR to the Cobb as the vibrations on the AWR 70a were more than I liked.
 


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