So what's the deal with the 2K-rpm rattle?

[Shifting_Gears]

Took the advise from another member here to do this, around 4k on an on ramp in 2nd (M6 car) and hit it. Smiles for the next few freeway miles. Want axle backs because the stocks look cheap but they sound soooo good I just can't. Only did an X pipe. Also, if you drive with the rear seat backs folded down, you hear more goodness in the cabin.

My stress relieving drives usually involve seats down.

It also gives a bigger whiff of spent fuel into the cabin, lol.

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[Elp_jc]

I have the 6sp manual, and curiously, it doesn't happen in 5th or 6th.

Are you sure? It could be due to wind/road noise at those higher speeds, no? Mine is also manual, and I couldn't hear it in higher gears either... but that doesn't mean it's not there. I need to try to duplicate it when engine is fully warmed up. But cold and in quiet mode, I definitely heard it loud and clear, from about 2,300 to 2,700 rpm or so.

 

[Elp_jc]

How can you be sure without a camera inside the engine compartment? At higher speeds, road and wind noise drown out other noises, so you might not be able to hear them, but that doesn't mean they're not there. These are not Bentleys, brother. Ha ha. It'd be extremely rare to be what you're describing; that's all . But if you believe it, that's okay. Thank you for posting that.

 

[Soulja4187]

Like I said before this isnt a fuel pump issue, how can a pump turning on sound like cans rattling. There was a TSB for the F150 5.0 where they pointed it to the VCT and said it was normal. The V6 Accord was notorious for making this sound. When it first started happening they thought it was the torque converter as the rattle was mostly around 2k RPM. Get used to it as this has been an issue with many motors that have the VCT.

 

[Elp_jc]

Nobody is talking about the deceleration rattle man; it's absolutely normal with the Borg Warner cam phasers. And it happens at any rpm. I only heard it ONCE on my F-150, when trying to duplicate it on purpose. I haven't heard it on my Bullitt, but I'm sure it's there too, since our intake cam phasers are Borg Warner too (the 3.5EB's all 4 are BW).

What we're talking about here is the CONSTANT rattle from around 2,300 to 2,800 rpm. And it apparently happens cold or hot. I don't know what it is, but I can tell you that noise is not the cam phasers, because they're not operating constantly, and certainly not under steady throttle, which is exactly what this rattle does.

 

[Vlad Soare]

So how does this 2k rattle actually sound? Does anyone have a link to a video where we can hear precisely this particular rattle, and not the DI injectors or cam phasers or anything like that?

Also, since the dual injection was brought up, how does it work? Is it exclusively PI below a certain rpm, exclusively DI above a certain rpm, and possibly an overlap (i.e. both PI and DI) in a narrow rpm range?
Or do they always work together, the exact split between them being adjusted continously, depending on load, throttle position and maybe other criteria?

 

[ice445]

So how does this 2k rattle actually sound? Does anyone have a link to a video where we can hear precisely this particular rattle, and not the DI injectors or cam phasers or anything like that?

Also, since the dual injection was brought up, how does it work? Is it exclusively PI below a certain rpm, exclusively DI above a certain rpm, and possibly an overlap (i.e. both PI and DI) in a narrow rpm range?
Or do they always work together, the exact split between them being adjusted continously, depending on load, throttle position and maybe other criteria?

I think the simplest explanation is that they always work together excluding idle where it's port injection only.

 

[Vlad Soare]

If that's the case, then the explanation that the 2k rattle might be caused by the DI taking over from the PI doesn't seem to hold water.

 

[ice445]

If that's the case, then the explanation that the 2k rattle might be caused by the DI taking over from the PI doesn't seem to hold water.

You know how some exhausts "drone" at certain RPM only, usually 2,000 RPM? It's a resonance effect caused by fluid dynamics. So why would the same thing not happen in a high pressure pump compressing fuel up to 14,000 PSI? That's the way I choose to look at it, especially since every car seems to make this noise. People are just over sensitive about it.

 

[Sivi70980]

Are you sure? It could be due to wind/road noise at those higher speeds, no? Mine is also manual, and I couldn't hear it in higher gears either... but that doesn't mean it's not there. I need to try to duplicate it when engine is fully warmed up. But cold and in quiet mode, I definitely heard it loud and clear, from about 2,300 to 2,700 rpm or so.

I've heard it in 5th gear on the one smooth road in my state...

 

[GT Pony]

So how does this 2k rattle actually sound? Does anyone have a link to a video where we can hear precisely this particular rattle, and not the DI injectors or cam phasers or anything like that?

You can hear it pretty good in this video.

 

[ihc95]

So how does this 2k rattle actually sound? Does anyone have a link to a video where we can hear precisely this particular rattle, and not the DI injectors or cam phasers or anything like that?

Also, since the dual injection was brought up, how does it work? Is it exclusively PI below a certain rpm, exclusively DI above a certain rpm, and possibly an overlap (i.e. both PI and DI) in a narrow rpm range?
Or do they always work together, the exact split between them being adjusted continously, depending on load, throttle position and maybe other criteria?

I believe the Gen 3 Coyote is unique in that it is exclusively PI below a certain rpm, and then transitions to DI around 2000 rpm. This is different than other dual injection engines (like from Toyota) where PI and DI are always blended and working together.

The transition to DI around 2k rpm is what I believe causes the "2k rattle."

 

[Vstang2]

You can hear it pretty good in this video.

Sounds exactly like mine under lite throttle at 2k-2300 RPM. Removing the sound tube actually knocked like 80% of the sound from coming into the cab now , doesn't sound near as bad anymore so im not worried.

 

[Osofast]

I think the easiest way to explain the sound is, almost replicates an older diesel motor to my ears it’s the same sound. I have it, I don’t worry about it.

 

[Elp_jc]

My car sounds exactly like the video above, and it starts just like it as well, which is around 2,300 rpm, not 2K. But in my car it lasts a lot longer. I heard it right outside the house, so engine was pretty cold (but ambient was like 80). I heard it from 2,300 to around 2,700. It'd be great if somebody with a Go-Pro could secure it inside the engine compartment. Go for a drive cold, then remove the camera before the engine compartment gets hot. Inside the car is already diluted, and hard to hear exactly how it sounds like. Oh, and since the suspicion is the DI is the culprit, put the GoPro as close as possible to the DI fuel pump on the rear passenger side.

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