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RMM and false knock?

Sourskittle

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#61
Totally ignored the newest style R32 Vw, srt challenger, and 2 mint condition fox body mustang GT's.

We're sorta car crazy :) we sell milk and bread, lol. (Publix supermarkets).
 


OP
C

Chuckable

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Thread Starter #63
A general description of how it works on this engine application, and specifics on how timing is retarded when knock is encountered would be useful. I imagine that as the engine runs up and down its rev range, and depending upon the conditions, if a RMM does cause a false knock it's only during a short window of time and the computer is able to react quickly. But, I'm just guessing.
 


razorlab

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#64
A general description of how it works on this engine application, and specifics on how timing is retarded when knock is encountered would be useful. I imagine that as the engine runs up and down its rev range, and depending upon the conditions, if a RMM does cause a false knock it's only during a short window of time and the computer is able to react quickly. But, I'm just guessing.
COBB explains it pretty well in a general high level here: https://cobb.app.box.com/ford-table-descriptions

The system does have a slow and fast way it reacts to information from the knock sensors with different strategies, decay rate, etc.

It's pretty tunable too, for better and worse.
 


Sourskittle

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#65
My passenger side motor mount was loose by 2.5 turns from when I sheared it at the track and replaced it. The bolt I used to replace it didn't have a shoulder like the stock bolt so I used the only washer I had that size. It had a rubber washer attached to the metal part as well. Turns out, the rubber couldn't handle it and checked out, leaving the mount bolt loose over time. No more false knock.
 


me32

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#68
My passenger side motor mount was loose by 2.5 turns from when I sheared it at the track and replaced it. The bolt I used to replace it didn't have a shoulder like the stock bolt so I used the only washer I had that size. It had a rubber washer attached to the metal part as well. Turns out, the rubber couldn't handle it and checked out, leaving the mount bolt loose over time. No more false knock.
Good to know.
 


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#69
My tuner is suggesting I have poor fuel, or false knock. We will eliminate the first possibility. What can you do to combat false knock?
 


dyn085

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#70
My tuner is suggesting I have poor fuel, or false knock. We will eliminate the first possibility. What can you do to combat false knock?
Re-torque your RMM bolts or put your OEM RMM back in. What RMM do you have?
 


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#71
I found a thread on the focus forums about this. So retorque the Cobb RMM, and check my intercooler. The levels fmic bolts up to the crash bar in front, and is direct metal on metal. I'll have to drop the front end again and check everything, add a rubber gromet to the metal bolts.
 


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